{"id":"GHSA-p7mv-53f2-4cwj","aliases":["GO-2024-3259"],"url":"https://o3.security/vulnerability/GHSA-p7mv-53f2-4cwj","summary":"CometBFT Vote Extensions: Panic when receiving a Pre-commit with an invalid data","details":"Name: ASA-2024-011: Vote Extensions: Panic when receiving a Pre-commit with an invalid data\nComponent: CometBFT\nCriticality: High (Considerable Impact, and Possible Likelihood per [ACMv1.2](https://github.com/interchainio/security/blob/main/resources/CLASSIFICATION_MATRIX.md))\nAffected versions: `>= 0.38.x`, unreleased `v1.x` and `main` development branches\nAffected users: Chain Builders + Maintainers, Validators\n\n### Impact\n\nA CometBFT node running in a network with [vote extensions][abci-spec] enabled could produce an invalid `Vote` message and send it to its peers. The invalid field of the `Vote` message is the `ValidatorIndex`, which identifies the sender in the `ValidatorSet` running that height of consensus. This field is ordinarily verified in the processing of `Vote` messages, but it turns out that in the case of a `Vote` message of type `Precommit` and for a non-`nil` `BlockID`, [a logic was introduced](https://github.com/cometbft/cometbft/blame/46621a87064b2ae235e122e66d9b22417b3aa35e/internal/consensus/state.go#L2357-L2364) before this ordinary verification to handle the attached vote extension. This introduced logic (not present in releases prior to `0.38.x`) does not double-check the validity of the `ValidatorIndex` field. The result is a panic in the execution of the node receiving and processing such message.\n\n#### Impact Qualification\nThis condition requires the introduction of malicious code in the full node sending this `Vote` message to its peers. Namely, nodes running upstream code cannot produce invalid `Vote` messages, with non-existing `ValidatorIndex`. Moreover, networks utilizing default behavior, where vote extensions are not enabled, are not affected by this issue.\n\n### Patches\n\nThe new CometBFT release [`v0.38.15`][v0.38.15] fixes this issue.\n\nUnreleased code in the `main` and `v1.x` branches, and experimental code in the `v0.38-experimental` and `v1.x-experimental` branches are patched as well.\n\n### Workarounds\n\nWhen the consensus code panics after receiving an invalid `Vote` message, the operator can identify the peer from which that message was received. This may require increasing the logging level of the `consensus` module. This peer can then be subsequently banned at the p2p layer as a temporary mitigation.  \n\n### References\n\n- [ABCI spec][abci-spec], in particular the operation of vote extensions\n- [Patched v0.38 release][v0.38.15]\n\n[abci-spec]: https://docs.cometbft.com/v0.38/spec/abci/abci++_basic_concepts\n[v0.38.15]: https://github.com/cometbft/cometbft/releases/tag/v0.38.15\n\n### Timeline\n\n* October 21, 2024, 3:26pm PST: Issue reported to the Cosmos Bug Bounty program\n* October 21, 2024, 3:41pm PST: Issue triaged by Amulet on-call, and distributed to Core team\n* October 29, 2024, 11:35pm PST: Core team completes validation of issue\n* October 30, 2024, 3:33am PST: Core team completes patch for issue\n* October 30, 2024, 5:09am PST: Amulet creates coordination plan; schedule for distribution\n* November 4, 2024, 8:00pm GMT: Pre-notification delivered\n* November 6, 2024, 8:00am GMT: Patch made available\n\n\nThis issue was reported by [corverroos](https://github.com/corverroos) to the Cosmos Bug Bounty Program on HackerOne on October 21, 2024. If you believe you have found a bug in the Interchain Stack or would like to contribute to the program by reporting a bug, please see https://hackerone.com/cosmos.\n\nIf you have questions about Interchain security efforts, please reach out to our official communication channel at [security@interchain.io](mailto:security@interchain.io).  For more information about the Interchain Foundation’s engagement with Amulet, and to sign up for security notification emails, please see https://github.com/interchainio/security.  \n\nA Github Security Advisory for this issue is available in the CometBFT [repository](https://github.com/cometbft/cometbft/security/advisories/GHSA-p7mv-53f2-4cwj). For more information about CometBFT, see https://docs.cometbft.com/.","published":"2024-11-06T15:33:55Z","modified":"2026-09-02T22:15:05.253906684Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/cometbft/cometbft","fixedVersion":"0.38.15"}],"fix":{"url":"https://github.com/cometbft/cometbft/commit/17d3bb66664cab6d6798c17e27198e15bbac1905","label":"cometbft/cometbft@17d3bb6"},"references":[{"type":"WEB","url":"https://github.com/cometbft/cometbft/security/advisories/GHSA-p7mv-53f2-4cwj"},{"type":"WEB","url":"https://github.com/cometbft/cometbft/commit/17d3bb66664cab6d6798c17e27198e15bbac1905"},{"type":"WEB","url":"https://docs.cometbft.com/v0.38/spec/abci/abci++_basic_concepts"},{"type":"PACKAGE","url":"https://github.com/cometbft/cometbft"},{"type":"WEB","url":"https://github.com/cometbft/cometbft/releases/tag/v0.38.15"},{"type":"WEB","url":"https://nrdax.com/techniques/NRDAX-T0211"},{"type":"WEB","url":"https://pkg.go.dev/vuln/GO-2024-3259"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-02T22:15:05.253906684Z"}}