netfilter: nf_conntrack_sip: don't use simple_strtoul
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_sip: don't use simple_strtoul Replace unsafe port parsing in epaddr_len(), ct_sip_parse_header_uri(), and ct_sip_parse_request() with a new sip_parse_port() helper that validates each digit against the buffer limit, eliminating the use of simple_strtoul() which assumes NUL-terminated strings. The previous code dereferenced pointers without bounds checks after sip_parse_addr() and relied on simple_strtoul() on non-NUL-terminated skb data. A port that reaches the buffer limit without a trailing character is also rejected as malformed. Also get rid of all simple_strtoul() usage in conntrack, prefer a stricter version instead. There are intentional changes: - Bail out if number is > UINT_MAX and indicate a failure, same for too long sequences. While we do accept 05535 as port 5535, we will not accept e.g. 'sip:10.0.0.1:005060'. While its syntactically valid under RFC 3261, we should restrict this to not waste cycles when presented with malformed packets with 64k '0' characters. - Force base 10 in ct_sip_parse_numerical_param(). This is used to fetch 'expire=' and 'rports='; both are expected to use base-10. - In nf_nat_sip.c, only accept the parsed value if its within the 1k-64k range. - epaddr_len now returns 0 if the port is invalid, as it already does for invalid ip addresses. This is intentional. nf_conntrack_sip performs lots of guesswork to find the right parts of the message to pars
CVE-2026-52986
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-2026-52986
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": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "8cd0358379570003659186706e077929d6930c40",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "9c6afcb1c3cbb2c0da65b8515ac14d7273872f84",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "b3264c977e79d8a25778d4fd11520f00fea1329c",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "ea2ecd29b8f4433e52607192ca91084f95787ca0",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "9f69c323ae0ab517e595c2cc74e0ae0d9d085611",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "7df9863bf538a626e8a684e59cb2c43eac0ef3c8",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "523762e3b6933fff81f01dfa3c60c0774044cdab",
"versionType": "git"
},
{
"status": "affected",
"version": "05e3ced297fe755093140e7487e292fb7603316e",
"lessThan": "8cf6809cddcbe301aedfc6b51bcd4944d45795f6",
"versionType": "git"
}
],
"programFiles": [
"net/netfilter/nf_conntrack_sip.c",
"net/netfilter/nf_nat_sip.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.26"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.26",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.258",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.209",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.175",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.141",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.91",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.33",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.0.10",
"versionType": "semver",
"lessThanOrEqual": "7.0.*"
},
{
"status": "unaffected",
"version": "7.1",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/nf_conntrack_sip.c",
"net/netfilter/nf_nat_sip.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-52986
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #40724 · Revision 1
- Added to Heist Feed
- Publisher date