CVE-2025-39946
Estado: AnalizadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
tls: make sure to abort the stream if headers are bogus
Normally we wait for the socket to buffer up the whole record before we service it. If the socket has a tiny buffer, however, we read out the data sooner, to prevent connection stalls. Make sure that we abort the connection when we find out late that the record is actually invalid. Retrying the parsing is fine in itself but since we copy some more data each time before we parse we can overflow the allocated skb space.
Constructing a scenario in which we're under pressure without enough data in the socket to parse the length upfront is quite hard. syzbot figured out a way to do this by serving us the header in small OOB sends, and then filling in the recvbuf with a large normal send.
Leer descripción completaMostrar menos
Make sure that tls_rx_msg_size() aborts strp, if we reach an invalid record there's really no way to recover.
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: 9.57%
- Percentil entre todas las CVEs puntuadas: 95
- 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 (1)
CWE
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/0aeb54ac4cd5cf8f60131b4d9ec0b6dc9c27b20d
- https://git.kernel.org/stable/c/208640e6225cc929a05adbf79d1df558add3e231
- https://git.kernel.org/stable/c/4cefe5be73886f383639fe0850bb72d5b568a7b9
- https://git.kernel.org/stable/c/61ca2da5fb8f433ce8bbd1657c84a86272133e6b
- https://git.kernel.org/stable/c/b36462146d86b1f22e594fe4dae611dffacfb203
JSON original (NVD)
Mostrar
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}
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