CVE-2026-45927 (GCVE-0-2026-45927)

Vulnerability from cvelistv5 – Published: 2026-05-27 12:17 – Updated: 2026-05-27 12:17
VLAI
Title
bpf: Require frozen map for calculating map hash
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Require frozen map for calculating map hash Currently, bpf_map_get_info_by_fd calculates and caches the hash of the map regardless of the map's frozen state. This leads to a TOCTOU bug where userspace can call BPF_OBJ_GET_INFO_BY_FD to cache the hash and then modify the map contents before freezing. Therefore, a trusted loader can be tricked into verifying the stale hash while loading the modified contents. Fix this by returning -EPERM if the map is not frozen when the hash is requested. This ensures the hash is only generated for the final, immutable state of the map.
Severity
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < 7752d36343862323bbeea4ce3adf0ec2ed86e122 (git)
Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < f415e114b58fe02c41191e47f24bdabb438daf72 (git)
Affected: ea2e6467ac36bf3d785defc89e58269b15d182f7 , < a2c86aa621c22f2a7e26c654f936d65cfff0aa91 (git)
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Linux Linux Affected: 6.18
Unaffected: 0 , < 6.18 (semver)
Unaffected: 6.18.14 , ≤ 6.18.* (semver)
Unaffected: 6.19.4 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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