CVE-2025-39847
In the Linux kernel, the following vulnerability has been resolved:
ppp: fix memory leak in pad_compress_skb
If alloc_skb() fails in pad_compress_skb(), it returns NULL without releasing the old skb. The caller does:
When pad_compress_skb() returns NULL, the reference to the old skb is lost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.
Align pad_compress_skb() semantics with realloc(): only free the old skb if allocation and compression succeed. At the call site, use the new_skb variable so the original skb is not lost when pad_compress_skb() fails.
Detalles técnicos trazas, registros y código del informe original
skb = pad_compress_skb(ppp, skb);
if (!skb)
goto drop;
drop:
kfree_skb(skb);CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.16%
- Percentil entre todas las CVEs puntuadas: 5
- 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).
Tecnologías afectadas (2)
CWE
- CWE-401
Referencias
- https://git.kernel.org/stable/c/0b21e9cd4559102da798bdcba453b64ecd7be7ee
- https://git.kernel.org/stable/c/1d8b354eafb8876d8bdb1bef69c7d2438aacfbe8
- https://git.kernel.org/stable/c/33a5bac5f14772730d2caf632ae97b6c2ee95044
- https://git.kernel.org/stable/c/4844123fe0b853a4982c02666cb3fd863d701d50
- https://git.kernel.org/stable/c/631fc8ab5beb9e0ec8651fb9875b9a968e7b4ae4
- https://git.kernel.org/stable/c/85c1c86a67e09143aa464e9bf09c397816772348
- https://git.kernel.org/stable/c/87a35a36742df328d0badf4fbc2e56061c15846c
- https://git.kernel.org/stable/c/9ca6a040f76c0b149293e430dabab446f3fc8ab7
- https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html
- https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html
- https://cert-portal.siemens.com/productcert/html/ssa-032379.html
JSON original (NVD)
Mostrar
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nppp: fix memory leak in pad_compress_skb\n\nIf alloc_skb() fails in pad_compress_skb(), it returns NULL without\nreleasing the old skb. The caller does:\n\n skb = pad_compress_skb(ppp, skb);\n if (!skb)\n goto drop;\n\ndrop:\n kfree_skb(skb);\n\nWhen pad_compress_skb() returns NULL, the reference to the old skb is\nlost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.\n\nAlign pad_compress_skb() semantics with realloc(): only free the old\nskb if allocation and compression succeed. At the call site, use the\nnew_skb variable so the original skb is not lost when pad_compress_skb()\nfails."
}
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