CVE-2026-45999
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.
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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 -t erofs -o cache_strategy=disabled foo.erofs /mnt $ dd if=/mnt/data of=/dev/null bs=4096 count=1
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H
- Puntuación base: 7.1
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1203Exploitation for Client Executionexecution75 % - Impacto principal
T1059Command and Scripting Interpreterexecution45 % - Impacto secundario
T1499.004Application or System Exploitationimpact65 %
Requiere interacción del usuario (UI:R) para montar imagen EROFS preparada. El underflow puede causar corrupción de memoria (lectura fuera de límites), potencialmente ejecución de código o DoS. CWE-191 (integer underflow).
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-191
Referencias
- https://git.kernel.org/stable/c/118ff71ff09ebaf323a09af9e911517321a299f4
- https://git.kernel.org/stable/c/21e161de2dc660b1bb70ef5b156ab8e6e1cca3ab
- https://git.kernel.org/stable/c/43a878639b90e9721ffa5eb616a7e6d8454adef3
- https://git.kernel.org/stable/c/778acd52e9497806fbd2cea7f770c41d6850fc48
- https://git.kernel.org/stable/c/bbbbb3f0d7864238a8da2a94cd6ec013fee06a2e
- https://git.kernel.org/stable/c/c9ce18e6bb2c467ec85756dc7989b547b7584fee
- https://git.kernel.org/stable/c/f1374fa6e57fd836623668d782ded9244cfd2938
JSON original (NVD)
Mostrar
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