DEBIAN-CVE-2026-52986

In the Linux kernel, the following vulnerability has been resolved:  netfilter: nfconntracksip: don't use simplestrtoul  Replace unsafe port parsing in epaddrlen(), ctsipparseheaderuri(), and ctsipparserequest() with a new sipparseport() helper that validates each digit against the buffer limit, eliminating the use of simplestrtoul() which assumes NUL-terminated strings.  The previous code dereferenced pointers without bounds checks after sipparseaddr() and relied on simplestrtoul() 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 simplestrtoul() usage in conntrack, prefer a stricter version instead.  There are intentional changes:  - Bail out if number is > UINTMAX 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 ctsipparsenumericalparam(). This is used to fetch   'expire=' and 'rports='; both are expected to use base-10.  - In nfnatsip.c, only accept the parsed value if its within the 1k-64k   range.  - epaddrlen now returns 0 if the port is invalid, as it already does   for invalid ip addresses.  This is intentional. nfconntracksip   performs lots of guesswork to find the right parts of the message   to parse.  Being stricter could break existing setups.   Connection tracking helpers are designed to allow traffic to   pass, not to block it.  Based on an earlier patch from Jenny Guanni Qu qguanni@gmail.com.