CVE-2026-45999
7.1 · HIGHOverview
CVE-2026-45999 is a high-severity vulnerability affecting linux linux_kernel. It was published on May 27, 2026 and has a CVSS 3.1 base score of 7.1 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.1, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical Description
In the Linux kernel, the following vulnerability has been resolved:
erofs: fix unsigned underflow in z_erofs_lz4_handle_overlap()
Some crafted images can have illegal (!partial_decoding &&
m_llen < m_plen) extents, and the LZ4 inplace decompression path
can be wrongly hit, but it cannot handle (outpages < inpages)
properly: "outpages - inpages" wraps to a large value and
the subsequent rq->out[] access reads past the decompressed_pages
array.
However, such crafted cases can correctly result in a corruption
report in the normal LZ4 non-inplace path.
Let's add an additional check to fix this for backporting.
Reproducible image (base64-encoded gzipped blob):
H4sIAJGR12kCA+3SPUoDQRgG4MkmkkZk8QRbRFIIi9hbpEjrHQI5ghfwCN5BLCzTGtLbBI+g
dilSJo1CnIm7GEXFxhT6PDDwfrs73/ywIQD/1ePD4r7Ou6ETsrq4mu7XcWfj++Pb58nJU/9i
PNtbjhan04/9GtX4qVYc814WDqt6FaX5s+ZwXXeq52lndT6IuVvlblytLMvh4Gzwaf90nsvz
2DF/21+20T/ldgp5s1jXRaN4t/8izsy/OUB6e/Qa79r+JwAAAAAAAL52vQVuGQAAAP6+my1w
ywAAAAAAAADwu14ATsEYtgBQAAA=
$ mount
Remediation
Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| linux | linux_kernel | >= 5.13, < 6.6.140 | Affected |
References
Frequently Asked Questions
What is CVE-2026-45999?
CVE-2026-45999 is a high-severity vulnerability affecting linux linux_kernel. It was published on May 27, 2026 and has a CVSS 3.1 base score of 7.1 (HIGH).
How severe is CVE-2026-45999?
This vulnerability has a CVSS 3.1 base score of 7.1, rated HIGH. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-45999?
Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-45999?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-45999 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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