An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A specially crafted smart contract code can cause an out-of-bounds read which can subsequently trigger an out-of-bounds write resulting in remote code execution. An attacker can create/send malicious smart contract to trigger this vulnerability.

An issue was discovered in EthereumJ 1.8.2. There is Unsafe Deserialization in ois.readObject in mine/Ethash.java and decoder.readObject in crypto/ECKey.java. When a node syncs and mines a new block, arbitrary OS commands can be run on the server.

Py-EVM v0.2.0-alpha.33 allows attackers to make a vm.executebytecode call that triggers computation.stack.values with '"stack": [100, 100, 0]' where b'\x' was expected, resulting in an execution failure because of an invalid opcode. This is reportedly related to "smart contracts can be executed indefinitely without gas being paid."

Impact

A vulnerable node can be forced to shutdown/crash using a specially crafted message. More details to be released later.

Patches

The problem is resolved in the v1.16.9 and v1.17.0 releases of Geth.

Credit

This issue was reported to the Ethereum Foundation Bug Bounty Program by Waleed Ahmed from vulsight.com

An exploitable information leak/denial of service vulnerability exists in the libevm (Ethereum Virtual Machine) create2 opcode handler of CPP-Ethereum. A specially crafted smart contract code can cause an out-of-bounds read leading to memory disclosure or denial of service. An attacker can create/send malicious a smart contract to trigger this vulnerability.

An exploitable improper authorization vulnerability exists in adminaddPeer API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). A JSON request can cause an access to the restricted functionality resulting in authorization bypass. An attacker can send JSON to trigger this vulnerability.

An exploitable improper authorization vulnerability exists in minerstop API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). An attacker can send JSON to trigger this vulnerability.

An exploitable improper authorization vulnerability exists in adminnodeInfo API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). A JSON request can cause an access to the restricted functionality resulting in authorization bypass. An attacker can send JSON to trigger this vulnerability.

An exploitable improper authorization vulnerability exists in minerstart API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). A JSON request can cause an access to the restricted functionality resulting in authorization bypass. An attacker can send JSON to trigger this vulnerability.

An exploitable improper authorization vulnerability exists in minersetEtherbase API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). A JSON request can cause an access to the restricted functionality resulting in authorization bypass.

An exploitable improper authorization vulnerability exists in minersetGasPrice API of cpp-ethereum's JSON-RPC (commit 4e1015743b95821849d001618a7ce82c7c073768). A JSON request can cause an access to the restricted functionality resulting in authorization bypass. An attacker can send JSON to trigger this vulnerability.

Impact

A vulnerable node, can be made to consume unbounded amounts of memory when handling specially crafted p2p messages sent from an attacker node.

Details

The p2p handler spawned a new goroutine to respond to ping requests. By flooding a node with ping requests, an unbounded number of goroutines can be created, leading to resource exhaustion and potentially crash due to OOM.

Patches

The fix is included in geth version 1.12.1-stable, i.e, 1.12.2-unstable and onwards.

Fixed by https://github.com/ethereum/go-ethereum/pull/27887

Workarounds

No known workarounds.

Credits

This bug was reported by Patrick McHardy and reported via bounty@ethereum.org.

References

Impact

An attacker can cause high CPU usage by sending a specially crafted p2p message. More details to be released later.

Credit

This issue was reported to the Ethereum Foundation Bug Bounty Program by @Yenya030

Impact

A vulnerable node can be forced to shutdown/crash using a specially crafted message. More details to be released later.

Credit

This issue was reported to the Ethereum Foundation Bug Bounty Program by DELENE TCHIO ROMUALD.

Impact

Through a flaw in the ECIES cryptography implementation, an attacker may be able to extract bits of the p2p node key.

Patches

The issue is resolved in the v1.16.9 and v1.17.0 releases of Geth. We recommend rotating the node key after applying the upgrade, which can be done by removing the file <datadir>/geth/nodekey before starting Geth.

Credit

The issue was reported as a public pull request to go-ethereum by @fengjian.

Impact

An attacker can cause high memory usage by sending a specially-crafted p2p message. More details to be released later.

Patches

The issue is resolved in the v1.17.0 release.

Credit

This issue was reported to the Ethereum Foundation Bug Bounty Program by @revofusion

A design flaw in Go-Ethereum 1.10.12 and older versions allows an attacker node to send 5120 future transactions with a high gas price in one message, which can purge all of pending transactions in a victim node's memory pool, causing a denial of service (DoS).

The GetBlockHeadersMsg handler in the LES protocol implementation in Go Ethereum (aka geth) before 1.8.11 may lead to an access violation because of an integer signedness error for the array index, which allows attackers to launch a Denial of Service attack by sending a packet with a -1 query.Skip value. The vulnerable remote node would be crashed by such an attack immediately, aka the EPoD (Ethereum Packet of Death) issue.

In Go Ethereum (aka geth) before 1.8.14, TraceChain in eth/apitracer.go does not verify that the end block is after the start block.

cmd/evm/runner.go in Go Ethereum (aka geth) allows attackers to cause a denial of service (SEGV) via crafted bytecode. Specific Go Packages Affected github.com/ethereum/go-ethereum/cmd/evm

Impact An ethash mining DAG generation flaw in Geth could cause miners to erroneously calculate PoW in an upcoming epoch (estimated early January, 2021). This happened on the ETC chain on 2020-11-06. This issue is relevant only for miners, non-mining nodes are unaffected.

Patches This issue is also fixed as of 1.9.24. Thanks to @slavikus for bringing the issue to our attention and writing the fix.

Workarounds This PR implements a patch: https://github.com/ethereum/go-ethereum/pull/21793

References https://blog.ethereum.org/2020/11/12/gethsecurityrelease/

For more information If you have any questions or comments about this advisory: Open an issue in go-ethereum Email us at security@ethereum.org

Geth (aka go-ethereum) through 1.13.4, when --http --graphql is used, allows remote attackers to cause a denial of service (memory consumption and daemon hang) via a crafted GraphQL query. NOTE: the vendor's position is that the "graphql endpoint [is not] designed to withstand attacks by hostile clients, nor handle huge amounts of clients/traffic.

Go Ethereum (aka geth) 1.8.19 allows attackers to cause a denial of service (memory consumption) by rewriting the length of a dynamic array in memory, and then writing data to a single memory location with a large index number, as demonstrated by use of "assembly { mstore }" followed by a "c[0xC800000] = 0xFF" assignment.

Impact Denial-of-service (crash) during block processing

Details

Affected versions suffer from a vulnerability which can be exploited through the MULMOD operation, by specifying a modulo of 0: mulmod(a,b,0), causing a panic in the underlying library. The crash was in the uint256 library, where a buffer underflowed.

if d == 0, dLen remains 0

and https://github.com/holiman/uint256/blob/4ce82e695c10ddad57215bdbeafb68b8c5df2c30/uint256.go#L451 will try to access index [-1].

The uint256 library was first merged in this commit, on 2020-06-08. Exploiting this vulnerabilty would cause all vulnerable nodes to drop off the network.

The issue was brought to our attention through a bug report, showing a panic occurring on sync from genesis on the Ropsten network. It was estimated that the least obvious way to fix this would be to merge the fix into uint256, make a new release of that library and then update the geth-dependency.

- https://github.com/holiman/uint256/releases/tag/v1.1.1 was made the same day, - PR to address the issue: https://github.com/holiman/uint256/pull/80 - PR to update geth deps: https://github.com/ethereum/go-ethereum/pull/21368

Patches

Upgrade to v1.9.18 or higher

Workarounds

Not at this time

References

https://blog.ethereum.org/2020/11/12/gethsecurityrelease/ For more information If you have any questions or comments about this advisory: Open an issue in go-ethereum Email us at security@ethereum.org

An exploitable unhandled exception vulnerability exists in multiple APIs of CPP-Ethereum JSON-RPC. Specially crafted JSON requests can cause an unhandled exception resulting in denial of service. An attacker can send malicious JSON to trigger this vulnerability.

A design flaw in all versions of Go-Ethereum allows an attacker node to send 5120 pending transactions of a high gas price from one account that all fully spend the full balance of the account to a victim Geth node, which can purge all of pending transactions in a victim node's memory pool and then occupy the memory pool to prevent new transactions from entering the pool, resulting in a denial of service (DoS).

Go-Ethereum v1.10.9 was discovered to contain an issue which allows attackers to cause a denial of service (DoS) via sending an excessive amount of messages to a node. This is caused by missing memory in the component /ethash/algorithm.go.

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the eth-account PyPI package, when an attacker is able to supply arbitrary input to the encodestructureddata method

Impact

A vulnerability in the Geth EVM could cause a node to reject the canonical chain.

Description

A memory-corruption bug within the EVM can cause a consensus error, where vulnerable nodes obtain a different stateRoot when processing a maliciously crafted transaction. This, in turn, would lead to the chain being split in two forks.

All Geth versions supporting the London hard fork are vulnerable (which predates London), so all users should update.

This bug was exploited on Mainnet at block 13107518, leading to a minority chain split.

Patches

A patch is included in the v1.10.8 release. The exact patch to fix the issue is contained within this commit

Workarounds

No workarounds exist, save to update and/or apply the patch commit.

References.

Post-mortem write-up.

Credits

The bug was found by @guidovranken (working for Sentnl during an audit of the Telos EVM) and reported via bounty@ethereum.org.

For more information If you have any questions or comments about this advisory:

Open an issue in go-ethereum Email us at security@ethereum.org

Impact This is a Consensus vulnerability, which can be used to cause a chain-split where vulnerable nodes reject the canonical chain.

Geth’s pre-compiled dataCopy (at 0x00...04) contract did a shallow copy on invocation. An attacker could deploy a contract that

- writes X to an EVM memory region R, - calls 0x00..04 with R as an argument, - overwrites R to Y, - and finally invokes the RETURNDATACOPY opcode.

When this contract is invoked, a consensus-compliant node would push X on the EVM stack, whereas Geth would push Y.

Patches

No standalone patches have been made.

Workarounds

Upgrade to 1.9.17 or higher.

References

https://blog.ethereum.org/2020/11/12/gethsecurityrelease/

For more information If you have any questions or comments about this advisory: Open an issue in go-ethereum Email us at security@ethereum.org