Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
Linux Linux — net: qrtr: Fix a refcount bug in qrtr_recvmsg()
AV AC PR UI S C I A CVSS EPSS %ile KEV
L L L N U N N H 5.5 .0015 4.6 —
AFFECTED
Product Versions Fixed
Linux 0a7e0d0ef05440db03c3199e84d228db943b237f – —
Linux 5.6 – 5.10.178
TIMELINE
Sep 17 Reserved by Linux
Sep 18 Published (CNA: Linux)
Aug 4 RESCORED — CVE-2023-53445 (Linux). CVSS 7.8 → 5.5 (NVD).
Description
In the Linux kernel, the following vulnerability has been resolved:
net: qrtr: Fix a refcount bug in qrtr_recvmsg()
Syzbot reported a bug as following:
refcount_t: addition on 0; use-after-free.
...
RIP: 0010:refcount_warn_saturate+0x17c/0x1f0 lib/refcount.c:25
...
Call Trace:
<TASK>
__refcount_add include/linux/refcount.h:199 [inline]
__refcount_inc include/linux/refcount.h:250 [inline]
refcount_inc include/linux/refcount.h:267 [inline]
kref_get include/linux/kref.h:45 [inline]
qrtr_node_acquire net/qrtr/af_qrtr.c:202 [inline]
qrtr_node_lookup net/qrtr/af_qrtr.c:398 [inline]
qrtr_send_resume_tx net/qrtr/af_qrtr.c:1003 [inline]
qrtr_recvmsg+0x85f/0x990 net/qrtr/af_qrtr.c:1070
sock_recvmsg_nosec net/socket.c:1017 [inline]
sock_recvmsg+0xe2/0x160 net/socket.c:1038
qrtr_ns_worker+0x170/0x1700 net/qrtr/ns.c:688
process_one_work+0x991/0x15c0 kernel/workqueue.c:2390
worker_thread+0x669/0x1090 kernel/workqueue.c:2537
It occurs in the concurrent scenario of qrtr_recvmsg() and
qrtr_endpoint_unregister() as following:
cpu0 cpu1
qrtr_recvmsg qrtr_endpoint_unregister
qrtr_send_resume_tx qrtr_node_release
qrtr_node_lookup mutex_lock(&qrtr_node_lock)
spin_lock_irqsave(&qrtr_nodes_lock, ) refcount_dec_and_test(&node->ref) [node->ref == 0]
radix_tree_lookup [node != NULL] __qrtr_node_release
qrtr_node_acquire spin_lock_irqsave(&qrtr_nodes_lock, )
kref_get(&node->ref) [WARNING] ...
mutex_unlock(&qrtr_node_lock)
Use qrtr_node_lock to protect qrtr_node_lookup() implementation, this
is actually improving the protection of node reference.
Lifecycle
Complete event history — 3 events, chronological
| Date | Event | Detail |
| September 17, 2025 | Reserved | Reserved by Linux |
| September 18, 2025 | Published | Published (CNA: Linux) |
| August 4, 2026 | RESCORED | RESCORED — CVE-2023-53445 (Linux). CVSS 7.8 → 5.5 (NVD). |
Affected
Affected products and packages — 2 rows
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
| Linux | Linux | — | 0a7e0d0ef05440db03c3199e84d228db943b237f | — |
| Linux | Linux | — | 5.6 | 5.10.178 |
About this page
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2023-53445 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.