CVE-2025-37756
In the Linux kernel, the following vulnerability has been resolved:
net: tls: explicitly disallow disconnect
syzbot discovered that it can disconnect a TLS socket and then run into all sort of unexpected corner cases. I have a vague recollection of Eric pointing this out to us a long time ago. Supporting disconnect is really hard, for one thing if offload is enabled we'd need to wait for all packets to be _acked_. Disconnect is not commonly used, disallow it.
The immediate problem syzbot run into is the warning in the strp, but that's just the easiest bug to trigger:
Detalles técnicos trazas, registros y código del informe original
WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 Call Trace: <TASK> tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363 tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043 inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678 sock_recvmsg_nosec net/socket.c:1023 [inline] sock_recvmsg+0x109/0x280 net/socket.c:1045 __sys_recvfrom+0x202/0x380 net/socket.c:2237
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: 0.29%
- Percentil entre todas las CVEs puntuadas: 20
- Fecha de la puntuación: 5/10/2026
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
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/2bcad8fefcecdd5f005d8c550b25d703c063c34a
- https://git.kernel.org/stable/c/5071a1e606b30c0c11278d3c6620cd6a24724cf6
- https://git.kernel.org/stable/c/7bdcf5bc35ae59fc4a0fa23276e84b4d1534a3cf
- https://git.kernel.org/stable/c/8513411ec321942bd3cfed53d5bb700665c67d86
- https://git.kernel.org/stable/c/9fcbca0f801580cbb583e9cb274e2c7fbe766ca6
- https://git.kernel.org/stable/c/ac91c6125468be720eafde9c973994cb45b61d44
- https://git.kernel.org/stable/c/c665bef891e8972e1d3ce5bbc0d42a373346a2c3
- https://git.kernel.org/stable/c/f3ce4d3f874ab7919edca364c147ac735f9f1d04
- http://www.openwall.com/lists/oss-security/2026/05/07/1
- https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
- https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html
JSON original (NVD)
Mostrar
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: tls: explicitly disallow disconnect\n\nsyzbot discovered that it can disconnect a TLS socket and then\nrun into all sort of unexpected corner cases. I have a vague\nrecollection of Eric pointing this out to us a long time ago.\nSupporting disconnect is really hard, for one thing if offload\nis enabled we'd need to wait for all packets to be _acked_.\nDisconnect is not commonly used, disallow it.\n\nThe immediate problem syzbot run into is the warning in the strp,\nbut that's just the easiest bug to trigger:\n\n WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486\n RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486\n Call Trace:\n <TASK>\n tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363\n tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043\n inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678\n sock_recvmsg_nosec net/socket.c:1023 [inline]\n sock_recvmsg+0x109/0x280 net/socket.c:1045\n __sys_recvfrom+0x202/0x380 net/socket.c:2237"
},
{
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"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: tls: explícitamente deshabilitar la desconexión. syzbot descubrió que puede desconectar un socket TLS y luego encontrarse con todo tipo de casos inesperados. Recuerdo vagamente que Eric nos lo señaló hace mucho tiempo. Admitir la desconexión es muy difícil; por ejemplo, si la descarga está habilitada, tendríamos que esperar a que se ackearan todos los paquetes. La desconexión no se usa comúnmente; deshabilitarla. El problema inmediato con el que se encuentra syzbot es la advertencia en el strp, pero ese es simplemente el error más fácil de activar: ADVERTENCIA: CPU: 0 PID: 5834 en net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 Rastreo de llamada: tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363 tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043 inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678 sock_recvmsg_nosec net/socket.c:1023 [en línea] sock_recvmsg+0x109/0x280 net/socket.c:1045 __sys_recvfrom+0x202/0x380 net/socket.c:2237"
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"lastModified": "2026-07-30T06:22:19.233",
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