netfilter: ipset: do not update comments from kernel-side hash adds
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.
CVE-2026-74492
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-2026-74492
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": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "6f13f4d52d06986c18f12e8bffaab944dd27ceab",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "f9d6cabff1fca010562dcdb0d22b296bdca3ba5a",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "16bfa7be2d76ca1e0aacfa363482e1bf8ab5042a",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "661ff9c0cfbe07f8eed920dde9f7781491738207",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "c710e9bf38e4e71a8db85d26a0f70c0674664207",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "4ae701848e4ba9e9713375fb7d82218cbd309da2",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "77dbb248a5cc7a5270cd37bbb0b635bf059a872a",
"versionType": "git"
},
{
"status": "affected",
"version": "f66ee0410b1c3481ee75e5db9b34547b4d582465",
"lessThan": "f30415929be8aeb002d557c8d3f7ab2d2188003a",
"versionType": "git"
},
{
"status": "affected",
"version": "5dd9488ae41070b69d2f4acb580f77db5705f9ca",
"versionType": "git"
},
{
"status": "affected",
"version": "a469bab3386aebff33c59506f3a95e35b91118fd",
"versionType": "git"
},
{
"status": "affected",
"version": "5.4.24",
"lessThan": "5.5",
"versionType": "semver"
},
{
"status": "affected",
"version": "5.5.8",
"lessThan": "5.6",
"versionType": "semver"
}
],
"programFiles": [
"net/netfilter/ipset/ip_set_hash_gen.h"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "5.6"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "5.6",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.265",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.216",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.183",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.151",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.103",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.44",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.8",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/ipset/ip_set_hash_gen.h"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74492
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #33179 · Revision 1
- Added to Heist Feed
- Publisher date