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PatchSiren cyber security CVE debrief

CVE-2026-43419 Linux CVE debrief

CVE-2026-43419 is a Linux kernel Ceph client bug that can leak memory in ceph_mdsc_build_path() when error paths fail to release a path buffer allocated with __getname(). The upstream fix adds the missing __putname() cleanup before returning when ownership is not transferred to the caller. This is primarily a stability and resource-consumption issue rather than a direct code-execution flaw.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-08
Original CVE updated
2026-05-12
Advisory published
2026-05-08
Advisory updated
2026-05-12

Who should care

Linux kernel maintainers, distro security teams, and operators running systems that use the Ceph client in kernel space should review this fix. Environments with heavy metadata/path handling activity are the most likely to notice resource impact from repeated leaks.

Technical summary

The vulnerability description states that ceph_mdsc_build_path() allocates a path buffer with __getname(), but some error code paths returned without freeing it. The fix ensures __putname() is called whenever the pointer is not handed off via path_info.path. Based on the supplied record, the issue is a memory leak in error handling for the Ceph filesystem path-building logic in the Linux kernel.

Defensive priority

Low to medium. The issue is an availability/resource-management problem with a published fix, but the supplied record does not indicate code execution, privilege escalation, or active exploitation.

Recommended defensive actions

  • Apply the Linux kernel patch that adds the missing __putname() cleanup in ceph_mdsc_build_path().
  • Prioritize rollout on systems that enable and actively use the Ceph client.
  • Monitor affected hosts for unusual memory growth or instability if patching is delayed.
  • Track kernel and distro advisories for backported fixes that correspond to the referenced upstream commits.
  • If you maintain downstream kernels, verify the fix is present in all supported branches that include the Ceph client code.

Evidence notes

The supplied CVE description explicitly says the fix resolves memory leaks in ceph_mdsc_build_path() by adding __putname() calls on error paths that did not free the path pointer obtained by __getname(). The NVD record provided in the corpus lists the vulnerability status as 'Undergoing Analysis' and includes five kernel.org stable commit references. No CVSS score, KEV entry, or weaponized exploitation information was provided in the source corpus.

Official resources

Published in the CVE record on 2026-05-08 and modified on 2026-05-12. No KEV listing is present in the supplied timeline, and the NVD record in the corpus is still marked 'Undergoing Analysis'.