vsock/vmci: fix sk_ack_backlog leak on failed handshake
Summary
| CVE | CVE-2026-53181 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-06-25 09:16:35 UTC |
| Updated | 2026-06-30 14:44:27 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: vsock/vmci: fix sk_ack_backlog leak on failed handshake When vmci_transport_recv_connecting_server() returns an error, vmci_transport_recv_listen() calls vsock_remove_pending() but never calls sk_acceptq_removed(). This leaves sk_ack_backlog incremented permanently. Repeated handshake failures (malformed packets, queue pair alloc failure, event subscribe failure) cause sk_ack_backlog to climb toward sk_max_ack_backlog. Once it reaches the limit the listener permanently refuses all new connections with -ECONNREFUSED, a silent denial of service requiring a process restart to recover. The two existing sk_acceptq_removed() calls in af_vsock.c do not cover this path: line 764 checks vsock_is_pending() which returns false after vsock_remove_pending(), and line 1889 is only reached on successful accept(). Fix by balancing sk_acceptq_added() with sk_acceptq_removed() on the error path. |
Risk And Classification
EPSS: 0.001840000 probability, percentile 0.082110000 (date 2026-07-01)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 22c587aa3ab1ab5264daff3ec32136fd30436c13 git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 cf7090e255d74c4b61c51f8ede9fcacdd8393b5b git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 ea0b03d52881c12a8c634ea0d6cbfa61cefdb488 git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 dfd853197615d322d3a88dbcab91fc0fd2096219 git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 bcb275626055df7f8f947f1a349754b4004d9a15 git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 ba9ad6015937a5e46ba1a31370e3efdec8abbdcc git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 9698582a4dd9c4a05889d7db96d4c0edc9e69cac git | Not specified |
| CNA | Linux | Linux | affected d021c344051af91f42c5ba9fdedc176740cbd238 c05fa14db43ebef3bd862ca9d073981c0358b3f0 git | Not specified |
| CNA | Linux | Linux | affected 3.9 | Not specified |
| CNA | Linux | Linux | unaffected 3.9 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.259 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.210 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.176 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.143 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.94 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.36 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.0.13 7.0.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/cf7090e255d74c4b61c51f8ede9fcacdd8393b5b | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/22c587aa3ab1ab5264daff3ec32136fd30436c13 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/9698582a4dd9c4a05889d7db96d4c0edc9e69cac | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/bcb275626055df7f8f947f1a349754b4004d9a15 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ea0b03d52881c12a8c634ea0d6cbfa61cefdb488 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/dfd853197615d322d3a88dbcab91fc0fd2096219 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ba9ad6015937a5e46ba1a31370e3efdec8abbdcc | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c05fa14db43ebef3bd862ca9d073981c0358b3f0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.