CVE-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 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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/7752d36343862323bbeea4ce3adf0ec2ed86e122	Patch
https://git.kernel.org/stable/c/a2c86aa621c22f2a7e26c654f936d65cfff0aa91	Patch
https://git.kernel.org/stable/c/f415e114b58fe02c41191e47f24bdabb438daf72	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2026-05-27 14:17

Updated : 2026-06-25 12:42

NVD link : CVE-2026-45927

Mitre link : CVE-2026-45927

CVE.ORG link : CVE-2026-45927

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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