CVE-2026-74492
In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: do not update comments from kernel-side hash adds mtype_resize() copies comment pointers with memcpy(), not the comment objects themselves.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.14%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: do not update comments from kernel-side hash adds mtype_resize() copies comment pointers with memcpy(), not the comment objects themselves. During the window after an entry has been copied but before the table swap and backlog replay, the old table is still published for packet-side updates while the replacement-table entry already holds the same ip_set_comment_rcu pointer. If xt_SET --add-set ... --exist hits that old entry in this window, mtype_add() calls ip_set_init_comment() even though packet-side adds carry no comment payload. That call frees the shared comment through the old entry, so the replacement-table entry now holds a stale pointer. When the queued add is replayed on the new table, mtype_add() calls ip_set_init_comment() again and strlen() dereferences the stale pointer. Fix this in mtype_add() by skipping ip_set_init_comment() when ext->target marks a packet-side add. Userspace adds still update comments, while packet-side adds can no longer free comment storage shared with a resize copy.
- CVSS 3.1
- 8.4 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.14% probability · 4th percentile
- CISA KEV
- Not listed
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/16bfa7be2d76ca1e0aacfa363482e1bf8ab5042a
- https://git.kernel.org/stable/c/4ae701848e4ba9e9713375fb7d82218cbd309da2
- https://git.kernel.org/stable/c/661ff9c0cfbe07f8eed920dde9f7781491738207
- https://git.kernel.org/stable/c/6f13f4d52d06986c18f12e8bffaab944dd27ceab
- https://git.kernel.org/stable/c/77dbb248a5cc7a5270cd37bbb0b635bf059a872a
- https://git.kernel.org/stable/c/c710e9bf38e4e71a8db85d26a0f70c0674664207
- https://git.kernel.org/stable/c/f30415929be8aeb002d557c8d3f7ab2d2188003a
- https://git.kernel.org/stable/c/f9d6cabff1fca010562dcdb0d22b296bdca3ba5a
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.