CVE-2026-23456
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case In decode_int(), the CONS case calls get_bits(bs, 2) to read a length value, then calls get_uint(bs, len) without checking that len bytes remain in the buffer. The existing boundary check only validates the 2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint() reads. This allows a malformed H.323/RAS packet to cause a 1-4 byte slab-out-of-bounds read. Add a boundary check for len bytes after get_bits() and before get_uint().
Severity
HIGH
CVSS score
8.2
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-04-03 16:16:32.300000
Last modified
2026-10-19 19:17:49.450000
View original CVE JSON
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"id": "CVE-2026-23456",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-04-03T16:16:32.300",
"lastModified": "2026-10-19T19:17:49.450",
"vulnStatus": "Modified",
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case\n\nIn decode_int(), the CONS case calls get_bits(bs, 2) to read a length\nvalue, then calls get_uint(bs, len) without checking that len bytes\nremain in the buffer. The existing boundary check only validates the\n2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint()\nreads. This allows a malformed H.323/RAS packet to cause a 1-4 byte\nslab-out-of-bounds read.\n\nAdd a boundary check for len bytes after get_bits() and before\nget_uint()."
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnetfilter: nf_conntrack_h323: corrección de lectura fuera de límites (OOB) en el caso CONS de decode_int()\n\nEn decode_int(), el caso CONS llama a get_bits(bs, 2) para leer un valor de longitud, luego llama a get_uint(bs, len) sin comprobar que len bytes permanezcan en el búfer. La comprobación de límites existente solo valida los 2 bits para get_bits(), no los 1-4 bytes subsiguientes que lee get_uint(). Esto permite que un paquete H.323/RAS malformado cause una lectura fuera de límites de slab de 1-4 bytes.\n\nAñadir una comprobación de límites para len bytes después de get_bits() y antes de get_uint()."
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