CVE-2021-21271: Github.com/tendermint/tendermint Remote Code Execution Vulnerability

{
  "schema_version" : "1.4.0",
  "id" : "GHSA-p658-8693-mhvg",
  "modified" : "2024-05-31T16:54:40Z",
  "published" : "2022-10-07T07:23:51Z",
  "aliases" : [ "CVE-2021-21271" ],
  "summary" : "Tendermint Core vulnerable to Uncontrolled Resource Consumption",
  "details" : "### Description \n\nTendermint Core v0.34.0 introduced a new way of handling evidence of misbehavior. As part of this, [we added a new `Timestamp` field to `Evidence` structs](https://github.com/tendermint/tendermint/pull/5219). This timestamp would be calculated using the same algorithm that is used when a block is created and proposed. (This algorithm relies on the timestamp of the last commit from this specific block.) \n\nIn Tendermint Core v0.34.0-v0.34.2, the `consensus` reactor is responsible for forming `DuplicateVoteEvidence` whenever double signs are observed. However, the current block is still “in flight” when it is being formed by the `consensus` reactor. It hasn’t been finalized through network consensus yet. This means that different nodes in the network may observe different “last commits” when assigning a timestamp to `DuplicateVoteEvidence.`\n\nIn turn, different nodes could form `DuplicateVoteEvidence` objects at the same height but with different timestamps. One `DuplicateVoteEvidence` object (with one timestamp) will then eventually get finalized in the block, but this means that any `DuplicateVoteEvidence` with a different timestamp is considered invalid. Any node that formed invalid `DuplicateVoteEvidence` will continue to propose invalid evidence; its peers may see this, and choose to disconnect from this node. This bug means that double signs are DoS vectors in Tendermint Core v0.34.0-v0.34.2. \n\nTendermint Core v0.34.3 is a security release which fixes this bug. As of v0.34.3, `DuplicateVoteEvidence` is no longer formed by the `consensus` reactor; rather, the `consensus` reactor passes the `Vote`s themselves into the `EvidencePool`, which is now responsible for forming `DuplicateVoteEvidence`. The `EvidencePool` has timestamp info that should be consistent across the network, which means that `DuplicateVoteEvidence` formed in this reactor should have consistent timestamps. \n\nThis release changes the API between the `consensus` and `evidence` reactors. \n\n### Impact\n\nThis is a denial-of-service vector which impacts networks running Tendermint Core v0.34.0 - v0.34.2.\n\n### Remediation\n\nThis problem has been patched in Tendermint Core v0.34.3. Networks running impacted versions of Tendermint Core should update immediately.\n\n### Workarounds\n\nThere are no workarounds, other than upgrading to a patched version of Tendermint Core.\n\n### Credits \n\n* Crypto.com (@cyril-crypto, @brianatcrypto, @tomtau and  @yihuang) for finding and submitting this vulnerability\n* @melekes and @cmwaters for identifying the root cause and patching the problem \n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [tendermint/tendermint](https://github.com/tendermint/tendermint)\n* Email us at [security@tendermint.com](mailto:security@tendermint.com)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/tendermint/tendermint"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.34.0"
      }, {
        "fixed" : "0.34.3"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/tendermint/tendermint/security/advisories/GHSA-p658-8693-mhvg"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-21271"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/tendermint/tendermint/pull/5219"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/tendermint/tendermint/commit/a2a6852ab99e4a0f9e79f0ea8c1726e262e25c76"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/tendermint/tendermint"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/tendermint/tendermint/blob/v0.34.3/CHANGELOG.md#v0.34.3"
  }, {
    "type" : "WEB",
    "url" : "https://pkg.go.dev/vuln/GO-2022-1052"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-10-07T07:23:51Z",
    "nvd_published_at" : null
  }
}