CVE-2026-46100
CVE-2026-46100 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- EPSS exploit prediction: 0% (3rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-32483
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
In the Linux kernel, the following vulnerability has been resolved: fs: afs: revert mmap_prepare() change Partially reverts commit 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()"). This is because the .mmap invocation establishes a refcount, but .mmap_prepare is called at a point where a merge or an allocation failure might happen after the call, which would leak the refcount increment. Functionality is being added to permit the use of .mmap_prepare in this case, but in the interim, we need to fix this.
Frequently asked questions
- What is CVE-2026-46100?
- In the Linux kernel, the following vulnerability has been resolved: fs: afs: revert mmap_prepare() change Partially reverts commit 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()"). This is because the .mmap invocation establishes a refcount, but .mmap_prepare is called at a point where a merge or an allocation failure might happen after the call, which would leak the refcount increment. Functionality is being added to permit the use of .mmap_prepare in this case, but in the interim, we need to fix this.
- How severe is CVE-2026-46100?
- CVE-2026-46100 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-46100 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-46100?
- CVE-2026-46100 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-46100?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-46100 have an EU (EUVD) identifier?
- Yes. CVE-2026-46100 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32483.
- When was CVE-2026-46100 published?
- CVE-2026-46100 was published on 2026-05-27 and last updated on 2026-06-25.
References
- https://git.kernel.org/stable/c/48c7a0eaeea41da17d1d84d2d7a4c40be122b246
- https://git.kernel.org/stable/c/f51f85c044809fbd39ac8ae07ac99bc43ce32bd5
- https://git.kernel.org/stable/c/fbfc6578eaca12daa0c09df1e9ba7f2c657b49da
Affected products (1)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
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