ghsa-7mv5-5mxh-qg88
Vulnerability from github
7.1 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N
Impact
Decoding a specifically formed message can cause invalid free()
or realloc()
calls if the message type contains an oneof
field, and the oneof
directly contains both a pointer field and a non-pointer field. If the message data first contains the non-pointer field and then the pointer field, the data of the non-pointer field is incorrectly treated as if it was a pointer value. Such message data rarely occurs in normal messages, but it is a concern when untrusted data is parsed.
Patches
Preliminary patch is available on git for 0.4.x and 0.3.x branches. The fix will be released in versions 0.3.9.8 and 0.4.5 once testing has been completed.
Workarounds
Following workarounds are available:
* Set the option no_unions
for the oneof field. This will generate fields as separate instead of C union, and avoids triggering the problematic code.
* Set the type of all fields inside the oneof to FT_POINTER
. This ensures that the data contained inside the union
is always a valid pointer.
* Heap implementations that guard against invalid free()
provide a partial mitigation. Depending on the message type, the pointer value may be attacker controlled and can be used to bypass heap protections.
References
Bug report: https://github.com/nanopb/nanopb/issues/647
For more information
If you have any questions or comments about this advisory, comment on the bug report linked above.
{ "affected": [ { "package": { "ecosystem": "PyPI", "name": "nanopb" }, "ranges": [ { "events": [ { "introduced": "0.3.2" }, { "fixed": "0.3.9.8" } ], "type": "ECOSYSTEM" } ] }, { "package": { "ecosystem": "PyPI", "name": "nanopb" }, "ranges": [ { "events": [ { "introduced": "0.4.0" }, { "fixed": "0.4.5" } ], "type": "ECOSYSTEM" } ] } ], "aliases": [ "CVE-2021-21401" ], "database_specific": { "cwe_ids": [ "CWE-763" ], "github_reviewed": true, "github_reviewed_at": "2024-08-30T18:45:41Z", "nvd_published_at": "2021-03-23T18:15:00Z", "severity": "HIGH" }, "details": "### Impact\nDecoding a specifically formed message can cause invalid `free()` or `realloc()` calls if the message type contains an `oneof` field, and the `oneof` directly contains both a pointer field and a non-pointer field. If the message data first contains the non-pointer field and then the pointer field, the data of the non-pointer field is incorrectly treated as if it was a pointer value. Such message data rarely occurs in normal messages, but it is a concern when untrusted data is parsed.\n\n### Patches\nPreliminary patch is available on git for [0.4.x](https://github.com/nanopb/nanopb/commit/e2f0ccf939d9f82931d085acb6df8e9a182a4261) and [0.3.x](https://github.com/nanopb/nanopb/commit/4a375a560651a86726e5283be85a9231fd0efe9c) branches. The fix will be released in versions 0.3.9.8 and 0.4.5 once testing has been completed.\n\n### Workarounds\nFollowing workarounds are available:\n* Set the option `no_unions` for the oneof field. This will generate fields as separate instead of C union, and avoids triggering the problematic code.\n* Set the type of all fields inside the oneof to `FT_POINTER`. This ensures that the data contained inside the `union` is always a valid pointer.\n* Heap implementations that guard against invalid `free()` provide a partial mitigation. Depending on the message type, the pointer value may be attacker controlled and can be used to bypass heap protections.\n\n### References\nBug report: https://github.com/nanopb/nanopb/issues/647\n\n### For more information\nIf you have any questions or comments about this advisory, comment on the bug report linked above.", "id": "GHSA-7mv5-5mxh-qg88", "modified": "2024-08-30T18:45:41Z", "published": "2024-08-30T18:45:41Z", "references": [ { "type": "WEB", "url": "https://github.com/nanopb/nanopb/security/advisories/GHSA-7mv5-5mxh-qg88" }, { "type": "ADVISORY", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-21401" }, { "type": "WEB", "url": "https://github.com/nanopb/nanopb/issues/647" }, { "type": "WEB", "url": "https://github.com/nanopb/nanopb/commit/4a375a560651a86726e5283be85a9231fd0efe9c" }, { "type": "WEB", "url": "https://github.com/nanopb/nanopb/commit/e2f0ccf939d9f82931d085acb6df8e9a182a4261" }, { "type": "PACKAGE", "url": "https://github.com/nanopb/nanopb" }, { "type": "WEB", "url": "https://github.com/nanopb/nanopb/blob/c9124132a604047d0ef97a09c0e99cd9bed2c818/CHANGELOG.txt#L1" }, { "type": "WEB", "url": "https://github.com/pypa/advisory-database/tree/main/vulns/nanopb/PYSEC-2021-432.yaml" } ], "schema_version": "1.4.0", "severity": [ { "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L", "type": "CVSS_V3" }, { "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N", "type": "CVSS_V4" } ], "summary": "nanopb vulnerable to invalid free() call with oneofs and PB_ENABLE_MALLOC" }
Sightings
Author | Source | Type | Date |
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Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.