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CVE-2026-22990 Linux CVE debrief

The Linux kernel has been updated to address a HIGH-severity vulnerability, CVE-2026-22990, in the libceph component. This vulnerability, with a CVSS score of 7.5, could allow an attacker to cause a denial of service (DoS) by providing a maliciously corrupted osdmap. The issue arises from the overzealous use of BUG_ON in the osdmap_apply_incremental() function, which could trigger unexpectedly and lead to a system crash. Instead of BUGing, the function now declares the incremental osdmap as invalid. Users should update their Linux kernel to the latest version to mitigate this vulnerability.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-01-23
Original CVE updated
2026-06-17
Advisory published
2026-01-23
Advisory updated
2026-06-17

Who should care

System administrators and users of Linux kernel versions prior to the patched versions should be aware of this vulnerability. This includes users of Linux distributions that have not yet updated their kernels to include the fix. The vulnerability could be exploited remotely, making it essential for administrators to update their systems promptly.

Technical summary

The vulnerability is located in the libceph component of the Linux kernel, specifically in the osdmap_apply_incremental() function. The function previously used BUG_ON to handle cases where the incremental osdmap epoch did not match the expected value. However, this approach could lead to system crashes if the osdmap was maliciously corrupted. The fix replaces BUG_ON with a check that declares the incremental osdmap as invalid in such cases, preventing the system from crashing.

Defensive priority

High

Recommended defensive actions

  • Update the Linux kernel to the latest version available.
  • Review and apply patches provided by the Linux kernel maintainers.
  • Ensure that systems are configured to receive and apply kernel updates automatically.
  • Monitor system logs for any suspicious activity related to the libceph component.
  • Consider implementing additional security measures, such as network segmentation and access controls, to limit the attack surface.
  • Regularly review and update system configurations to ensure they align with security best practices.

Evidence notes

The information provided is based on the CVE-2026-22990 record and related sources from the Linux kernel community. The vulnerability has been addressed through a series of patches applied to the Linux kernel. The patches are available on the Linux kernel Git repository.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-22990 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-22990

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-22990 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-22990

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/4b106fbb1c7b841cd402abd83eb2447164c799ea

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/6348d70af847b79805374fe628d3809a63fd7df3

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/6afd2a4213524bc742b709599a3663aeaf77193c

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/6c6cec3db3b418c4fdf815731bc39e46dff75e1b

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/9aa0b0c14cefece078286d78b97d4c09685e372d

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/d3613770e2677683e65d062da5e31f48c409abe9

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/e00c3f71b5cf75681dbd74ee3f982a99cb690c2b

    416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.