RUSTSEC-2026-0329
Vulnerability from osv_rustsec – Published: 2026-08-03 12:00 – Updated: 2026-10-07 08:23 – Source websiteThe automatically reseeding implementations of HMAC-DRBG would panic if called with a desired non-zero output length cleanly divisible by 65_536, the maximum number of output bytes that can be generated before reseeding has to happen.
Impact
An application relying on libcrux-hmac-drgb to provide randomness of byte length a non-zero integer multiple of 65_536 in a single call to fill_bytes would panic.
Any calls with output buffer lengths not cleanly divisible by 65_536 are not affected.
Mitigation
With release the release of version 0.0.2 of libcrux-hmac-drbg this bug has been fixed and reseeding DRBG implementations can be used with arbitrary output lengths.
We recommend users upgrade to libcrux-hmac-drbg version 0.0.2.
{
"affected": [
{
"database_specific": {
"categories": [],
"cvss": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"informational": null
},
"ecosystem_specific": {
"affected_functions": null,
"affects": {
"arch": [],
"functions": [
"libcrux_hmac_drbg::HmacDrbgRng::fill_bytes"
],
"os": []
}
},
"package": {
"ecosystem": "crates.io",
"name": "libcrux-hmac-drbg",
"purl": "pkg:cargo/libcrux-hmac-drbg"
},
"ranges": [
{
"events": [
{
"introduced": "0.0.0-0"
},
{
"fixed": "0.0.2"
}
],
"type": "SEMVER"
}
],
"versions": []
}
],
"aliases": [],
"database_specific": {
"license": "CC0-1.0"
},
"details": "The automatically reseeding implementations of HMAC-DRBG would panic if called with a desired non-zero output length cleanly divisible by `65_536`, the maximum number of output bytes that can be generated before reseeding has to happen.\n\n# Impact\n\nAn application relying on `libcrux-hmac-drgb` to provide randomness of byte length a non-zero integer multiple of `65_536` in a single call to `fill_bytes` would panic.\n\nAny calls with output buffer lengths not cleanly divisible by `65_536` are not affected.\n\n# Mitigation\n\nWith release the release of version `0.0.2` of `libcrux-hmac-drbg` this bug has been fixed and reseeding DRBG implementations can be used with arbitrary output lengths.\n\nWe recommend users upgrade to `libcrux-hmac-drbg` version `0.0.2`.",
"id": "RUSTSEC-2026-0329",
"modified": "2026-10-07T08:23:44Z",
"published": "2026-08-03T12:00:00Z",
"references": [
{
"type": "PACKAGE",
"url": "https://crates.io/crates/libcrux-hmac-drbg"
},
{
"type": "ADVISORY",
"url": "https://rustsec.org/advisories/RUSTSEC-2026-0329.html"
},
{
"type": "WEB",
"url": "https://github.com/celabshq/libcrux/pull/1558"
}
],
"related": [],
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "Auto-Reseeding HMAC-DRBG could panic for some output lengths"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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