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TI-2026-38451 Aliases CVE-2026-53365GHSA-9p63-4jq7-2c9w

vsock/virtio: fix zerocopy completion for multi-skb sends

Priority HIGH 69CWE-404Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-404.

Summary

In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: fix zerocopy completion for multi-skb sends When a large message is fragmented into multiple skbs, the zerocopy uarg is only allocated and attached to the last skb in the loop. Non-final skbs carry pinned user pages with no completion tracking, so the kernel has no way to notify userspace when those pages are safe to reuse. If the loop breaks early the uarg is never allocated at all, leaking pinned pages with no completion notification. Fix this by following the approach used by TCP: allocate the zerocopy uarg (if not provided by the caller) before the send loop and attach it to every skb via skb_zcopy_set(), which takes a reference per skb. Each skb's completion properly decrements the refcount, and the notification only fires after the last skb is freed. On failure, if no data was sent, the uarg is cleanly aborted via net_zcopy_put_abort(). This issue was initially discovered by sashiko while reviewing commit 1cb36e252211 ("vsock/virtio: fix MSG_ZEROCOPY pinned-pages accounting") but was pre-existing.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00197 9th percentileScored 2026-11-07
Fix Fixed Linux (Linux): 6.12.97, 6.18.34, 7.0.11 +1Red Hat: 2 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.7 and later6.12.97, 6.18.34, 7.0.11, 7.1Patch availableCNA
  • Linux VendorLinux Affected 6.7 and later Fixed in 6.12.97, 6.18.34, 7.0.11, 7.1 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.7 to before 6.18.34; 6.19 to before 7.0.11VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*7.1 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*7.1 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:*7.1 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:*7.1 rc4VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.7 to before 6.18.34; 6.19 to before 7.0.11 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* Versions 7.1 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* Versions 7.1 rc4 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.12.97, 6.18.34, 7.0.11, 7.1

Red Hat 2 advisories

  • RHSA-2026:77689 Released 2026-10-08 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.56.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.56.1.el9_8, kernel-64k-devel-5.14.0-687.56.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.56.1.el9_8, kernel-64k-5.14.0-687.56.1.el9_8, kernel-64k-core-5.14.0-687.56.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.56.1.el9_8, libperf-5.14.0-687.56.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.56.1.el9_8, kernel-rt-64k-5.14.0-687.56.1.el9_8, kernel-rt-64k-core-5.14.0-687.56.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.56.1.el9_8, kernel-rt-core-5.14.0-687.56.1.el9_8, kernel-rt-debug-5.14.0-687.56.1.el9_8 +9
  • RHSA-2026:77690 Released 2026-10-08 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • 10Base-SMTV kernel-modules-internal-6.12.0-211.64.1.el10_2
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.64.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.64.1.el10_2, kernel-64k-devel-6.12.0-211.64.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.64.1.el10_2, kernel-64k-6.12.0-211.64.1.el10_2, kernel-64k-core-6.12.0-211.64.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.64.1.el10_2, libperf-6.12.0-211.64.1.el10_2
    • Red Hat Enterprise Linux Hidden (v. 10) kernel-modules-internal-6.12.0-211.64.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.64.1.el10_2, kernel-rt-64k-6.12.0-211.64.1.el10_2, kernel-rt-64k-core-6.12.0-211.64.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.64.1.el10_2, kernel-rt-core-6.12.0-211.64.1.el10_2, kernel-rt-debug-6.12.0-211.64.1.el10_2 +9

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
10Base-SMTVFixed RHSA-2026:77690
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:77689
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:77689
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:77689
Red Hat Enterprise Linux Hidden (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:77689
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:77690
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:77689
Not affected: 4 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-53365
  2. 2026-10-03 Alias added: GHSA-9p63-4jq7-2c9w
  3. 2026-10-09 Fix available: RHSA-2026:77689 · Red Hat
  4. 2026-10-09 Fix available: RHSA-2026:77690 · Red Hat
  5. 2026-10-09 Fix available: 10Base-SMTV, Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux AppStream (v. 9) +9 · Red Hat
  6. 2026-10-30 Affected versions changed · Red Hat

References

Patch 3

Other 1

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences