GHSA-723Q-C22R-GXFR
Vulnerability from github – Published: 2026-08-15 06:32 – Updated: 2026-08-17 06:33In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject exclusive maps as inner maps in map-in-map
An exclusive map (created with excl_prog_hash) is bound to a single program by hash: check_map_prog_compatibility() refuses to load any program whose digest does not match map->excl_prog_sha. That check only runs for maps a program references directly, i.e. its used_maps. A map reached at runtime through a map-of-maps is never in used_maps, and bpf_map_meta_equal() does not consider excl_prog_sha, so an exclusive map can be inserted into a non-exclusive outer map and then looked up and mutated by an unrelated program, bypassing the exclusivity guarantee.
For the signed loader this defeats the metadata map exclusivity check added in the signed loader: the cached map->sha[] is validated against the signed hash while another program on a hostile host rewrites the frozen map's contents through the outer map.
{
"affected": [],
"aliases": [
"CVE-2026-74364"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-15T06:22:38Z",
"severity": "HIGH"
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject exclusive maps as inner maps in map-in-map\n\nAn exclusive map (created with excl_prog_hash) is bound to a single\nprogram by hash: check_map_prog_compatibility() refuses to load any\nprogram whose digest does not match map-\u003eexcl_prog_sha. That check\nonly runs for maps a program references directly, i.e. its used_maps.\nA map reached at runtime through a map-of-maps is never in used_maps,\nand bpf_map_meta_equal() does not consider excl_prog_sha, so an\nexclusive map can be inserted into a non-exclusive outer map and\nthen looked up and mutated by an unrelated program, bypassing the\nexclusivity guarantee.\n\nFor the signed loader this defeats the metadata map exclusivity check\nadded in the signed loader: the cached map-\u003esha[] is validated against\nthe signed hash while another program on a hostile host rewrites the\nfrozen map\u0027s contents through the outer map.",
"id": "GHSA-723q-c22r-gxfr",
"modified": "2026-08-17T06:33:40Z",
"published": "2026-08-15T06:32:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74364"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/3a0f73d27a8d379a8852a378b3c3208143e3b3b2"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7c58ace08f180f8e249e714d1623388362f9d807"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/9a3c3c49c333760c8944dadacbe114c1884546ef"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.