TeacherCat Token

Unable to find manual contract audit (e.g. Certik, PeckShield, Solidity...)

TeacherCat.addLiquidity(uint256,uint256) (#795-808) sends eth to arbitrary user
Dangerous calls:
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
Ensure that an arbitrary user cannot withdraw unauthorized funds.

Additional information: link

Reentrancy in TeacherCat._transfer(address,address,uint256) (#693-742):
External calls:
- swapAndLiquify(contractTokenBalance) (#716)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
External calls sending eth:
- swapAndLiquify(contractTokenBalance) (#716)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- _balances[sender] = _balances[sender].sub(amount,Insufficient Balance) (#719)
- finalAmount = takeFee(sender,recipient,amount) (#730)
- _balances[address(this)] = _balances[address(this)].add(feeAmount) (#822)
- _balances[recipient] = _balances[recipient].add(finalAmount) (#736)
- addBot(recipient) (#727)
- _isBlacklisted[recipient] = true (#682)
Apply the check-effects-interactions pattern.

Additional information: link

Combination 1: Reentrancy vulnerabilities + Functions that send Ether to arbitraty destination. Usual for scams. May be justified by some complex mechanics (e.g. rebase, reflections). DYOR & manual audit are advised.

TeacherCat.addLiquidity(uint256,uint256) (#795-808) ignores return value by uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
Ensure that all the return values of the function calls are used.

Additional information: link

TeacherCat.allowance(address,address).owner (#527) shadows:
- Ownable.owner() (#154-156) (function)
TeacherCat._approve(address,address,uint256).owner (#550) shadows:
- Ownable.owner() (#154-156) (function)
Rename the local variables that shadow another component.

Additional information: link

TeacherCat.setBuyTaxes(uint256,uint256,uint256) (#575-581) should emit an event for:
- _totalTaxIfBuying = _buyLiquidityFee.add(_buyMarketingFee).add(_buyTeamFee) (#580)
TeacherCat.setSellTaxes(uint256,uint256,uint256) (#583-589) should emit an event for:
- _totalTaxIfSelling = _sellLiquidityFee.add(_sellMarketingFee).add(_sellTeamFee) (#588)
TeacherCat.setDistributionSettings(uint256,uint256,uint256) (#591-597) should emit an event for:
- _liquidityShare = newLiquidityShare (#592)
- _teamShare = newTeamShare (#594)
- _totalDistributionShares = _liquidityShare.add(_marketingShare).add(_teamShare) (#596)
TeacherCat.setMaxTxAmount(uint256) (#599-601) should emit an event for:
- _maxTxAmount = maxTxAmount (#600)
TeacherCat.setWalletLimit(uint256) (#611-613) should emit an event for:
- _walletMax = newLimit (#612)
TeacherCat.setNumTokensBeforeSwap(uint256) (#615-617) should emit an event for:
- minimumTokensBeforeSwap = newLimit (#616)
TeacherCat.setKillBlock(uint256) (#685-687) should emit an event for:
- killblock = num (#686)
Emit an event for critical parameter changes.

Additional information: link

TeacherCat.setMarketingWalletAddress(address).newAddress (#619) lacks a zero-check on :
- marketingWalletAddress = address(newAddress) (#620)
TeacherCat.setTeamWalletAddress(address).newAddress (#623) lacks a zero-check on :
- teamWalletAddress = address(newAddress) (#624)
Check that the address is not zero.

Additional information: link

Reentrancy in TeacherCat.changeRouterVersion(address) (#644-661):
External calls:
- newPairAddress = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this),_uniswapV2Router.WETH()) (#652-653)
State variables written after the call(s):
- isMarketPair[address(uniswapPair)] = true (#660)
- isWalletLimitExempt[address(uniswapPair)] = true (#659)
- uniswapPair = newPairAddress (#656)
- uniswapV2Router = _uniswapV2Router (#657)
Reentrancy in TeacherCat.constructor(string,string) (#474-505):
External calls:
- uniswapPair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this),_uniswapV2Router.WETH()) (#481-482)
State variables written after the call(s):
- _allowances[address(this)][address(uniswapV2Router)] = _totalSupply (#485)
- _balances[_msgSender()] = _totalSupply (#503)
- _totalDistributionShares = _liquidityShare.add(_marketingShare).add(_teamShare) (#492)
- _totalTaxIfBuying = _buyLiquidityFee.add(_buyMarketingFee).add(_buyTeamFee) (#490)
- _totalTaxIfSelling = _sellLiquidityFee.add(_sellMarketingFee).add(_sellTeamFee) (#491)
- isExcludedFromFee[owner()] = true (#487)
- isExcludedFromFee[address(this)] = true (#488)
- isMarketPair[address(uniswapPair)] = true (#501)
- isTxLimitExempt[owner()] = true (#498)
- isTxLimitExempt[address(this)] = true (#499)
- isWalletLimitExempt[owner()] = true (#494)
- isWalletLimitExempt[address(uniswapPair)] = true (#495)
- isWalletLimitExempt[address(this)] = true (#496)
- uniswapV2Router = _uniswapV2Router (#484)
Reentrancy in TeacherCat.swapAndLiquify(uint256) (#751-773):
External calls:
- swapTokensForEth(tokensForSwap) (#756)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
External calls sending eth:
- transferToAddressETH(marketingWalletAddress,amountBNBMarketing) (#766)
- recipient.transfer(amount) (#641)
- transferToAddressETH(teamWalletAddress,amountBNBTeam) (#769)
- recipient.transfer(amount) (#641)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- _allowances[owner][spender] = amount (#554)
Reentrancy in TeacherCat.transferFrom(address,address,uint256) (#671-675):
External calls:
- _transfer(sender,recipient,amount) (#672)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
External calls sending eth:
- _transfer(sender,recipient,amount) (#672)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- _approve(sender,_msgSender(),_allowances[sender][_msgSender()].sub(amount,ERC20: transfer amount exceeds allowance)) (#673)
- _allowances[owner][spender] = amount (#554)
Apply the check-effects-interactions pattern.

Additional information: link

Reentrancy in TeacherCat._transfer(address,address,uint256) (#693-742):
External calls:
- swapAndLiquify(contractTokenBalance) (#716)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
External calls sending eth:
- swapAndLiquify(contractTokenBalance) (#716)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
Event emitted after the call(s):
- Transfer(sender,address(this),feeAmount) (#823)
- finalAmount = takeFee(sender,recipient,amount) (#730)
- Transfer(sender,recipient,finalAmount) (#738)
Reentrancy in TeacherCat.constructor(string,string) (#474-505):
External calls:
- uniswapPair = IUniswapV2Factory(_uniswapV2Router.factory()).createPair(address(this),_uniswapV2Router.WETH()) (#481-482)
Event emitted after the call(s):
- Transfer(address(0),_msgSender(),_totalSupply) (#504)
Reentrancy in TeacherCat.swapAndLiquify(uint256) (#751-773):
External calls:
- swapTokensForEth(tokensForSwap) (#756)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
External calls sending eth:
- transferToAddressETH(marketingWalletAddress,amountBNBMarketing) (#766)
- recipient.transfer(amount) (#641)
- transferToAddressETH(teamWalletAddress,amountBNBTeam) (#769)
- recipient.transfer(amount) (#641)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
Event emitted after the call(s):
- Approval(owner,spender,amount) (#555)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
Reentrancy in TeacherCat.swapTokensForEth(uint256) (#775-793):
External calls:
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
Event emitted after the call(s):
- SwapTokensForETH(tokenAmount,path) (#792)
Reentrancy in TeacherCat.transferFrom(address,address,uint256) (#671-675):
External calls:
- _transfer(sender,recipient,amount) (#672)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
- uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount,0,path,address(this),block.timestamp) (#784-790)
External calls sending eth:
- _transfer(sender,recipient,amount) (#672)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
Event emitted after the call(s):
- Approval(owner,spender,amount) (#555)
- _approve(sender,_msgSender(),_allowances[sender][_msgSender()].sub(amount,ERC20: transfer amount exceeds allowance)) (#673)
Apply the check-effects-interactions pattern.

Additional information: link

Ownable.unlock() (#189-194) uses timestamp for comparisons
Dangerous comparisons:
- require(bool,string)(block.timestamp > _lockTime,Contract is locked until 7 days) (#191)
Avoid relying on block.timestamp.

Additional information: link

Address.isContract(address) (#85-94) uses assembly
- INLINE ASM (#92)
Address._functionCallWithValue(address,bytes,uint256,string) (#121-138) uses assembly
- INLINE ASM (#130-133)
Do not use evm assembly.

Additional information: link

Address._functionCallWithValue(address,bytes,uint256,string) (#121-138) is never used and should be removed
Address.functionCall(address,bytes) (#104-106) is never used and should be removed
Address.functionCall(address,bytes,string) (#108-110) is never used and should be removed
Address.functionCallWithValue(address,bytes,uint256) (#112-114) is never used and should be removed
Address.functionCallWithValue(address,bytes,uint256,string) (#116-119) is never used and should be removed
Address.isContract(address) (#85-94) is never used and should be removed
Address.sendValue(address,uint256) (#96-102) is never used and should be removed
Context._msgData() (#12-15) is never used and should be removed
SafeMath.mod(uint256,uint256) (#73-75) is never used and should be removed
SafeMath.mod(uint256,uint256,string) (#77-80) is never used and should be removed
Remove unused functions.

Additional information: link

TeacherCat._totalSupply (#438) is set pre-construction with a non-constant function or state variable:
- 10 ** 15 * 10 ** _decimals
TeacherCat._maxTxAmount (#439) is set pre-construction with a non-constant function or state variable:
- 10 ** 15 * 10 ** _decimals
TeacherCat._walletMax (#440) is set pre-construction with a non-constant function or state variable:
- 10 ** 15 * 10 ** _decimals
TeacherCat.minimumTokensBeforeSwap (#441) is set pre-construction with a non-constant function or state variable:
- 10 ** 9 * 10 ** _decimals
Remove any initialization of state variables via non-constant state variables or function calls. If variables must be set upon contract deployment, locate initialization in the constructor instead.

Additional information: link

Low level call in Address.sendValue(address,uint256) (#96-102):
- (success) = recipient.call{value: amount}() (#100)
Low level call in Address._functionCallWithValue(address,bytes,uint256,string) (#121-138):
- (success,returndata) = target.call{value: weiValue}(data) (#124)
Avoid low-level calls. Check the call success. If the call is meant for a contract, check for code existence

Additional information: link

Function IUniswapV2Pair.DOMAIN_SEPARATOR() (#228) is not in mixedCase
Function IUniswapV2Pair.PERMIT_TYPEHASH() (#229) is not in mixedCase
Function IUniswapV2Pair.MINIMUM_LIQUIDITY() (#245) is not in mixedCase
Function IUniswapV2Router01.WETH() (#264) is not in mixedCase
Function TeacherCat.Launch() (#558-561) is not in mixedCase
Parameter TeacherCat.setSwapAndLiquifyEnabled(bool)._enabled (#627) is not in mixedCase
Variable TeacherCat._balances (#413) is not in mixedCase
Variable TeacherCat._buyLiquidityFee (#422) is not in mixedCase
Variable TeacherCat._buyMarketingFee (#423) is not in mixedCase
Variable TeacherCat._buyTeamFee (#424) is not in mixedCase
Variable TeacherCat._sellLiquidityFee (#426) is not in mixedCase
Variable TeacherCat._sellMarketingFee (#427) is not in mixedCase
Variable TeacherCat._sellTeamFee (#428) is not in mixedCase
Variable TeacherCat._liquidityShare (#430) is not in mixedCase
Variable TeacherCat._marketingShare (#431) is not in mixedCase
Variable TeacherCat._teamShare (#432) is not in mixedCase
Variable TeacherCat._totalTaxIfBuying (#434) is not in mixedCase
Variable TeacherCat._totalTaxIfSelling (#435) is not in mixedCase
Variable TeacherCat._totalDistributionShares (#436) is not in mixedCase
Variable TeacherCat._maxTxAmount (#439) is not in mixedCase
Variable TeacherCat._walletMax (#440) is not in mixedCase
Follow the Solidity naming convention.

Additional information: link

Redundant expression "this (#13)" inContext (#6-16)
Remove redundant statements if they congest code but offer no value.

Additional information: link

Reentrancy in TeacherCat._transfer(address,address,uint256) (#693-742):
External calls:
- swapAndLiquify(contractTokenBalance) (#716)
- recipient.transfer(amount) (#641)
External calls sending eth:
- swapAndLiquify(contractTokenBalance) (#716)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- _balances[sender] = _balances[sender].sub(amount,Insufficient Balance) (#719)
- finalAmount = takeFee(sender,recipient,amount) (#730)
- _balances[address(this)] = _balances[address(this)].add(feeAmount) (#822)
- _balances[recipient] = _balances[recipient].add(finalAmount) (#736)
- addBot(recipient) (#727)
- _isBlacklisted[recipient] = true (#682)
Event emitted after the call(s):
- Transfer(sender,address(this),feeAmount) (#823)
- finalAmount = takeFee(sender,recipient,amount) (#730)
- Transfer(sender,recipient,finalAmount) (#738)
Reentrancy in TeacherCat.swapAndLiquify(uint256) (#751-773):
External calls:
- transferToAddressETH(marketingWalletAddress,amountBNBMarketing) (#766)
- recipient.transfer(amount) (#641)
- transferToAddressETH(teamWalletAddress,amountBNBTeam) (#769)
- recipient.transfer(amount) (#641)
External calls sending eth:
- transferToAddressETH(marketingWalletAddress,amountBNBMarketing) (#766)
- recipient.transfer(amount) (#641)
- transferToAddressETH(teamWalletAddress,amountBNBTeam) (#769)
- recipient.transfer(amount) (#641)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
- _allowances[owner][spender] = amount (#554)
Event emitted after the call(s):
- Approval(owner,spender,amount) (#555)
- addLiquidity(tokensForLP,amountBNBLiquidity) (#772)
Reentrancy in TeacherCat.transferFrom(address,address,uint256) (#671-675):
External calls:
- _transfer(sender,recipient,amount) (#672)
- recipient.transfer(amount) (#641)
External calls sending eth:
- _transfer(sender,recipient,amount) (#672)
- recipient.transfer(amount) (#641)
- uniswapV2Router.addLiquidityETH{value: ethAmount}(address(this),tokenAmount,0,0,deadAddress,block.timestamp) (#800-807)
State variables written after the call(s):
- _approve(sender,_msgSender(),_allowances[sender][_msgSender()].sub(amount,ERC20: transfer amount exceeds allowance)) (#673)
- _allowances[owner][spender] = amount (#554)
Event emitted after the call(s):
- Approval(owner,spender,amount) (#555)
- _approve(sender,_msgSender(),_allowances[sender][_msgSender()].sub(amount,ERC20: transfer amount exceeds allowance)) (#673)
Apply the check-effects-interactions pattern.

Additional information: link

Variable IUniswapV2Router01.addLiquidity(address,address,uint256,uint256,uint256,uint256,address,uint256).amountADesired (#269) is too similar to IUniswapV2Router01.addLiquidity(address,address,uint256,uint256,uint256,uint256,address,uint256).amountBDesired (#270)
Prevent variables from having similar names.

Additional information: link

TeacherCat.slitherConstructorVariables() (#397-830) uses literals with too many digits:
- deadAddress = 0x000000000000000000000000000000000000dEaD (#411)
Use: Ether suffix, Time suffix, or The scientific notation

Additional information: link

TeacherCat._decimals (#404) should be constant
Add the constant attributes to state variables that never change.

Additional information: link

waiveOwnership() should be declared external:
- Ownable.waiveOwnership() (#163-166)
transferOwnership(address) should be declared external:
- Ownable.transferOwnership(address) (#168-172)
getUnlockTime() should be declared external:
- Ownable.getUnlockTime() (#174-176)
getTime() should be declared external:
- Ownable.getTime() (#178-180)
lock(uint256) should be declared external:
- Ownable.lock(uint256) (#182-187)
unlock() should be declared external:
- Ownable.unlock() (#189-194)
name() should be declared external:
- TeacherCat.name() (#507-509)
symbol() should be declared external:
- TeacherCat.symbol() (#511-513)
decimals() should be declared external:
- TeacherCat.decimals() (#515-517)
totalSupply() should be declared external:
- TeacherCat.totalSupply() (#519-521)
allowance(address,address) should be declared external:
- TeacherCat.allowance(address,address) (#527-529)
increaseAllowance(address,uint256) should be declared external:
- TeacherCat.increaseAllowance(address,uint256) (#531-534)
decreaseAllowance(address,uint256) should be declared external:
- TeacherCat.decreaseAllowance(address,uint256) (#536-539)
minimumTokensBeforeSwapAmount() should be declared external:
- TeacherCat.minimumTokensBeforeSwapAmount() (#541-543)
approve(address,uint256) should be declared external:
- TeacherCat.approve(address,uint256) (#545-548)
Launch() should be declared external:
- TeacherCat.Launch() (#558-561)
setMarketPairStatus(address,bool) should be declared external:
- TeacherCat.setMarketPairStatus(address,bool) (#563-565)
setIsExcludedFromFee(address,bool) should be declared external:
- TeacherCat.setIsExcludedFromFee(address,bool) (#571-573)
setSwapAndLiquifyEnabled(bool) should be declared external:
- TeacherCat.setSwapAndLiquifyEnabled(bool) (#627-630)
setSwapAndLiquifyByLimitOnly(bool) should be declared external:
- TeacherCat.setSwapAndLiquifyByLimitOnly(bool) (#632-634)
getCirculatingSupply() should be declared external:
- TeacherCat.getCirculatingSupply() (#636-638)
changeRouterVersion(address) should be declared external:
- TeacherCat.changeRouterVersion(address) (#644-661)
transfer(address,uint256) should be declared external:
- TeacherCat.transfer(address,uint256) (#666-669)
transferFrom(address,address,uint256) should be declared external:
- TeacherCat.transferFrom(address,address,uint256) (#671-675)
isBlackList(address) should be declared external:
- TeacherCat.isBlackList(address) (#677-679)
setKillBlock(uint256) should be declared external:
- TeacherCat.setKillBlock(uint256) (#685-687)
writeBlackList(address,bool) should be declared external:
- TeacherCat.writeBlackList(address,bool) (#689-691)
Use the external attribute for functions never called from the contract.

Additional information: link

Average 30d PancakeSwap liquidity is less than $100. Token is either dead or inactive.

Average 30d PancakeSwap volume is less than $100. Token is either dead or inactive.

Average 30d number of PancakeSwap swaps is less than 1. Token is either dead or inactive.

Average PancakeSwap trading volume, liqudity, number of swaps are extremely low. Token seems to be dead.

Number of Binance Smart Chain (BSC) token holders is low.

Token is deployed only at one blockchain

Token has only one trading pair

Contract has 10% buy tax and 10% sell tax.
Taxes are low and contract ownership is renounced.

Unable to find website, listings and other project-related information

Young tokens have high risks of scam / price dump / death

Token has no active CoinGecko listing / rank

Token has no active CoinMarketCap listing / rank