CVE-2026-45927
published 2026-05-27CVE-2026-45927: 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…
medium6.3
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.
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| linux | linux | — | — |
| linux | linux | >= ea2e6467ac36bf3d785defc89e58269b15d182f7 < 7752d36343862323bbeea4ce3adf0ec2ed86e122 | 7752d36343862323bbeea4ce3adf0ec2ed86e122 |
| linux | linux | >= ea2e6467ac36bf3d785defc89e58269b15d182f7 < f415e114b58fe02c41191e47f24bdabb438daf72 | f415e114b58fe02c41191e47f24bdabb438daf72 |
| linux | linux | >= ea2e6467ac36bf3d785defc89e58269b15d182f7 < a2c86aa621c22f2a7e26c654f936d65cfff0aa91 | a2c86aa621c22f2a7e26c654f936d65cfff0aa91 |
| linux | linux_kernel | — | — |