CVEvulnerability
CVE-2024-50038
5.5 MEDIUM
Official page ↗
- Status
- Modified
- Published
- 2024-10-21
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Description
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xtables: avoid NFPROTO_UNSPEC where needed
syzbot managed to call xt_cluster match via ebtables:
WARNING: CPU: 0 PID: 11 at net/netfilter/xt_cluster.c:72 xt_cluster_mt+0x196/0x780
[..]
ebt_do_table+0x174b/0x2a40
Module registers to NFPROTO_UNSPEC, but it assumes ipv4/ipv6 packet
processing. As this is only useful to restrict locally terminating
TCP/UDP traffic, register this for ipv4 and ipv6 family only.
Pablo points out that this is a general issue, direct users of the
set/getsockopt interface can call into targets/matches that were only
intended for use with ip(6)tables.
Check all UNSPEC matches and targets for similar issues:
- matches and targets are fine except if they assume skb_network_header()
is valid -- this is only true when called from inet layer: ip(6) stack
pulls the ip/ipv6 header into linear data area.
- targets that return XT_CONTINUE or other xtables verdicts must be
restricted too, they are incompatbile with the ebtables traverser, e.g.
EBT_CONTINUE is a completely different value than XT_CONTINUE.
Most matches/targets are changed to register for NFPROTO_IPV4/IPV6, as
they are provided for use by ip(6)tables.
The MARK target is also used by arptables, so register for NFPROTO_ARP too.
While at it, bail out if connbytes fails to enable the corresponding
conntrack family.
This change passes the selftests in iptables.git.
Affected configurations
• linux linux kernel (>= 2.6.30 < 5.15.168)
• linux linux kernel (>= 5.16 < 6.1.113)
• linux linux kernel (>= 6.2 < 6.6.57)
• linux linux kernel (>= 6.7 < 6.11.4)
• linux linux kernel 6.12
References
- https://git.kernel.org/stable/c/0bfcb7b71e735560077a42847f69597ec7dcc326 Patch
- https://git.kernel.org/stable/c/4cdc55ec6222bb195995cc58f7cb46e4d8907056 Patch
- https://git.kernel.org/stable/c/85ff9a0f793ca52c527e75cd40a69c948627ebde Patch
- https://git.kernel.org/stable/c/8f482bb7e27b37f1f734bb9a8eeb28b23d59d189 Patch
- https://git.kernel.org/stable/c/997f67d813ce0cf5eb3cdb8f124da68141e91b6c Patch
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html lists.debian.org