ZeroDay Findings
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2026-43489

In the Linux kernel, the following vulnerability has been resolved: liveupdate: luo_file: remember retrieve() status LUO keeps track of successful retrieve attempts on…

Published May 13, 2026 · catalog updated Jun 26, 2026 · linux linux kernel

Severity
Medium5.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.1%
Remediation
Advisory link
Affected products
cpe linux/linux kernel

In the Linux kernel, the following vulnerability has been resolved: liveupdate: luo_file: remember retrieve() status LUO keeps track of successful retrieve attempts on a LUO file. It does so to avoid multiple retrievals of the same file. Multiple retrievals cause problems because once the file is retrieved, the serialized data structures are likely freed and the file is likely in a very different state from what the code expects. The retrieve boolean in struct luo_file keeps track of this, and is passed to the finish callback so it knows what work was already done and what it has left to do. All this works well when retrieve succeeds. When it fails, luo_retrieve_file() returns the error immediately, without ever storing anywhere that a retrieve was attempted or what its error code was. This results in an errored LIVEUPDATE_SESSION_RETRIEVE_FD ioctl to userspace, but nothing prevents it from trying this again. The retry is problematic for much of the same reasons listed above. The file is likely in a very different state than what the retrieve logic normally expects, and it might even have freed some serialization data structures. Attempting to access them or free them again is going to break things. For example, if memfd managed to restore 8 of its 10 folios, but fails on the 9th, a subsequent retrieve attempt will try to call kho_restore_folio() on the first folio again, and that will fail with a warning since it is an invalid operation. Apart from the retry, finish() also breaks. Since on failure the retrieved bool in luo_file is never touched, the finish() call on session close will tell the file handler that retrieve was never attempted, and it will try to access or free the data structures that might not exist, much in the same way as the retry attempt. There is no sane way of attempting the retrieve again. Remember the error retrieve returned and directly return it on a retry. Also pass this status code to finish() so it can make the right decision on the work

Technical analysis

Mechanism and impact are interpreted from ingested advisories — not independent exploit research.

  • CWE classification

    No CWE identifiers stored yet.

  • Prerequisites and impact

    Follow the original vendor advisory for access prerequisites and impact. This catalog does not invent exploit conditions.

How to fix CVE-2026-43489

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2026-43489 is a medium public vulnerability record for linux linux kernel. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether linux linux kernel is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: linux/linux kernel; linux/linux kernel (7.0). Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 5.5 (technical impact); EPSS 0.1% (30-day exploitation probability). It is not currently listed in the CISA Known Exploited catalog. Sources contributing to this record: cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Related intelligence

  • Exploitation evidence

    Not listed as known exploited in CISA KEV. Not in CISA KEV or VulnCheck KEV.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. May 13, 2026 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: liveupdate: luo_file: remember retrieve() status LUO keeps track of successful retrieve attempts on a LUO file. It does so to avoid multiple retrievals of the same file. Multiple retrievals cause problems because once the file is retrieved, the serialized data structures are likely freed and the file is likely in a very different

  2. Jun 26, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: liveupdate: luo_file: remember retrieve() status LUO keeps track of successful retrieve attempts on a LUO file. It does so to avoid multiple retrievals of the same file. Multiple retrievals cause problems because once the file is retrieved, the serialized data structures are likely freed and the file is likely in a very different

Affected versions

Enter an installed version to get a verified affected / not-affected result against the ranges below.

  • cpe linux/linux kernelversion unspecified
  • cpe linux/linux kernel7.0

Sources

  • CVE.orgVulnerability recordCVE-2026-43489

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-43489

    30-day exploitation probability 0.1%

    first.org
  • NIST NVDVulnerability recordCVE-2026-43489

    In the Linux kernel, the following vulnerability has been resolved: liveupdate: luo_file: remember retrieve() status LUO keeps track of successful retrieve attempts on a LUO file. It does so to avoid multiple retrievals of the same file. Multiple retrievals cause problems bec

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.