PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-43058 Linux CVE debrief

CVE-2026-43058 is a Linux kernel media/vidtv issue resolved by changing two helper functions to accept const pointers instead of pass-by-value structs. The source says the previous calling convention copied struct contents, including MemorySanitizer shadow and origin metadata, which could trigger uninitialized-value warnings. The published CVE record is dated 2026-05-02 and was modified on 2026-05-06.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-05-02
Original CVE updated
2026-05-06
Advisory published
2026-05-02
Advisory updated
2026-05-06

Who should care

Linux kernel maintainers, distro kernel teams, and engineers who build or test kernels with MemorySanitizer enabled should pay attention, especially if they backport media subsystem fixes. This is most relevant for environments tracking kernel stability, CI noise reduction, and downstream maintenance of the vidtv code path.

Technical summary

The reported defect is in vidtv_ts_null_write_into() and vidtv_ts_pcr_write_into(), which took their struct arguments by value. That copying behavior can bring MSAN shadow/origin metadata along with the stack copy and lead to uninit-value reports. The fix makes both parameters const pointers, which avoids the unnecessary copy and enforces that the functions do not modify the structs.

Defensive priority

Low. The source describes a sanitizer-triggering correctness issue rather than a demonstrated exploit path or data-corruption scenario.

Recommended defensive actions

  • Backport the upstream Linux kernel fix to any maintained branches that include the affected vidtv code.
  • Verify that both vidtv_ts_null_write_into() and vidtv_ts_pcr_write_into() use const pointer parameters in downstream trees.
  • Run MemorySanitizer-enabled kernel tests after patching to confirm the uninitialized-value warnings are resolved.
  • If you maintain kernel CI, treat this as a build/test hygiene fix and include it in routine stable update review for the media subsystem.

Evidence notes

The CVE record from NVD is marked "Undergoing Analysis" in the supplied source item. The Linux kernel description states that vidtv_ts_null_write_into() and vidtv_ts_pcr_write_into() took structs by value, causing MSAN uninit-value warnings, and that the fix is to pass const pointers instead. The reference list in the NVD record points to Linux kernel stable commit URLs as the supporting upstream fix evidence.

Official resources

Public CVE record published 2026-05-02T07:16:20.830Z and modified 2026-05-06T13:08:07.970Z. The supplied NVD source item lists the vulnerability status as Undergoing Analysis.