In the Linux kernel, the following vulnerability has been resolved:

af_unix: Fix garbage collector racing against connect()

Garbage collector does not take into account the risk of embryo getting
enqueued during the garbage collection. If such embryo has a peer that
carries SCM_RIGHTS, two consecutive passes of scan_children() may see a
different set of children. Leading to an incorrectly elevated inflight
count, and then a dangling pointer within the gc_inflight_list.

sockets are AF_UNIX/SOCK_STREAM
S is an unconnected socket
L is a listening in-flight socket bound to addr, not in fdtable
V's fd will be passed via sendmsg(), gets inflight count bumped

connect(S, addr) sendmsg(S, [V]); close(V) __unix_gc()
---------------- ------------------------- -----------

NS = unix_create1()
skb1 = sock_wmalloc(NS)
L = unix_find_other(addr)
unix_state_lock(L)
unix_peer(S) = NS
// V count=1 inflight=0

NS = unix_peer(S)
skb2 = sock_alloc()
skb_queue_tail(NS, skb2[V])

// V became in-flight
// V count=2 inflight=1

close(V)

// V count=1 inflight=1
// GC candidate condition met

for u in gc_inflight_list:
if (total_refs == inflight_refs)
add u to gc_candidates

// gc_candidates={L, V}

for u in gc_candidates:
scan_children(u, dec_inflight)

// embryo (skb1) was not
// reachable from L yet, so V's
// inflight remains unchanged
__skb_queue_tail(L, skb1)
unix_state_unlock(L)
for u in gc_candidates:
if (u.inflight)
scan_children(u, inc_inflight_move_tail)

// V count=1 inflight=2 (!)

If there is a GC-candidate listening socket, lock/unlock its state. This
makes GC wait until the end of any ongoing connect() to that socket. After
flipping the lock, a possibly SCM-laden embryo is already enqueued. And if
there is another embryo coming, it can not possibly carry SCM_RIGHTS. At
this point, unix_inflight() can not happen because unix_gc_lock is already
taken. Inflight graph remains unaffected.

Project Subscriptions

Vendors Products
Debian Linux Subscribe
Linux Kernel Subscribe
Enterprise Linux Subscribe
Rhel Aus Subscribe
Rhel E4s Subscribe
Rhel Eus Subscribe
Rhel Tus Subscribe
Advisories
Source ID Title
Debian DLA Debian DLA DLA-3840-1 linux security update
Debian DLA Debian DLA DLA-3842-1 linux-5.10 security update
Debian DSA Debian DSA DSA-5680-1 linux security update
Debian DSA Debian DSA DSA-5681-1 linux security update
Ubuntu USN Ubuntu USN USN-6893-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6893-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6893-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6895-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6895-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6895-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6895-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-5 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6898-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6898-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6898-3 Linux kernel kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6898-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6900-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6917-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6918-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6919-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6926-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6926-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6926-3 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-6927-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6938-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7019-1 Linux kernel vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 23 Dec 2025 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Debian
Debian debian Linux
Linux
Linux linux Kernel
CPEs cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.9:rc3:*:*:*:*:*:*
Vendors & Products Debian
Debian debian Linux
Linux
Linux linux Kernel
Metrics cvssV3_1

{'score': 7.0, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H'}

cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Fri, 11 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00076}

epss

{'score': 0.00078}


Fri, 22 Nov 2024 12:00:00 +0000


Tue, 05 Nov 2024 10:45:00 +0000


Wed, 30 Oct 2024 15:30:00 +0000

Type Values Removed Values Added
CPEs cpe:/a:redhat:enterprise_linux:9
cpe:/o:redhat:enterprise_linux:9

Wed, 02 Oct 2024 15:00:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel Aus
Redhat rhel E4s
Redhat rhel Tus
CPEs cpe:/o:redhat:rhel_aus:8.6
cpe:/o:redhat:rhel_e4s:8.6
cpe:/o:redhat:rhel_tus:8.6
Vendors & Products Redhat rhel Aus
Redhat rhel E4s
Redhat rhel Tus

Tue, 24 Sep 2024 11:15:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:enterprise_linux:8
cpe:/o:redhat:rhel_eus:8.8

Tue, 24 Sep 2024 06:30:00 +0000

Type Values Removed Values Added
First Time appeared Redhat enterprise Linux
CPEs cpe:/a:redhat:enterprise_linux:8::nfv
Vendors & Products Redhat enterprise Linux

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T08:59:47.874Z

Reserved: 2024-02-19T14:20:24.194Z

Link: CVE-2024-26923

cve-icon Vulnrichment

Updated: 2024-08-02T00:21:05.612Z

cve-icon NVD

Status : Analyzed

Published: 2024-04-25T06:15:57.160

Modified: 2025-12-23T19:08:35.743

Link: CVE-2024-26923

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-04-24T00:00:00Z

Links: CVE-2024-26923 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses