netfilter: nf_conntrack_h323: check for zero length in DecodeQ931()
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: check for zero length in DecodeQ931() In DecodeQ931(), the UserUserIE code path reads a 16-bit length from the packet, then decrements it by 1 to skip the protocol discriminator byte before passing it to DecodeH323_UserInformation(). If the encoded length is 0, the decrement wraps to -1, which is then passed as a large value to the decoder, leading to an out-of-bounds read. Add a check to ensure len is positive after the decrement.
CVE-2026-23455
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-23455
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "2121f5fbe88daff0f1fc5bc47d359426c74b86b0",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "65fa92f79677858b14b9e4b7275f26639afe2710",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "495e97af9e7249ee02b72bb1d0848a6efc3700f4",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "f5e4f4e4cdb75ec36802059a94195a31f193da60",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "633e8f87dad32263f6a57dccdb873f042c062111",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "9d00fe7d6d7c5b5f1065a6e042b54f2e44bd6df8",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "b652b05d51003ac074b912684f9ec7486231717b",
"versionType": "git"
},
{
"status": "affected",
"version": "5e35941d990123f155b02d5663e51a24f816b6f3",
"lessThan": "f173d0f4c0f689173f8cdac79991043a4a89bf66",
"versionType": "git"
}
],
"programFiles": [
"net/netfilter/nf_conntrack_h323_asn1.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.253",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.203",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.167",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.130",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.78",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.20",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.10",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/nf_conntrack_h323_asn1.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-23455
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #39856 · Revision 1
- Added to Heist Feed
- Publisher date