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

tun: free page on build_skb failure in tun_xdp_one()

When build_skb() fails in tun_xdp_one(), the function sets ret to
-ENOMEM and jumps to the out label, which returns without freeing the
page that vhost_net_build_xdp() allocated for the frame. As with the
short-frame rejection path, tun_sendmsg() discards the per-buffer error
and still returns total_len, so vhost_tx_batch() takes the success path
and never frees the page. Each build_skb() failure in a batch leaks one
page-frag chunk.

Free the page before taking the error path, matching the put_page() the
other error exits of tun_xdp_one() already perform.
Published: 2026-06-09
Score: 7.1 High
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Impact

A failure in the Linux kernel tun_xdp_one() function causes build_skb() to return an error without freeing the page that was allocated for the frame. Each such failure leaks one page-frag chunk from kernel memory, which over time can exhaust available memory and lead to a denial‑of‑service scenario. The impact is limited to loss of memory resources and does not provide direct code execution or access to secrets.

Affected Systems

All Linux kernel builds that include the tun module and employ XDP for virtual networking are affected. Because the patch was applied in a later kernel commit, any kernel version prior to that commit is vulnerable; no specific version numbers are listed, so treat all earlier releases as susceptible.

Risk and Exploitability

The EPSS score is < 1%, and the vulnerability is not listed in CISA KEV, so publicly documented exploitation probability remains very low. The CVSS score is 7.1, indicating a high impact primarily due to memory resource exhaustion. The likely attack vector is local privileged access or could be remote if an attacker can repeatedly trigger build_skb() failures via crafted XDP programs on tun interfaces.

Generated by OpenCVE AI on June 14, 2026 at 06:52 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Apply a kernel update that includes the patch freeing the page on build_skb failure; target kernel commits newer than 4fefc6156a162a9f50035c12091a5e5130c82c6e.
  • Disable XDP on tun interfaces if a kernel upgrade is not yet available, e.g., ip link set dev <tun> xdp off.
  • Consider disabling the tun module entirely if the functionality is not required, or use an alternative virtual networking solution that does not rely on XDP for tun.

Generated by OpenCVE AI on June 14, 2026 at 06:52 UTC.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Debian DSA Debian DSA DSA-6355-1 linux security update
History

Fri, 19 Jun 2026 12:45:00 +0000


Sun, 14 Jun 2026 05:45:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H'}


Wed, 10 Jun 2026 02:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-459
CWE-724

Wed, 10 Jun 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-772
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Tue, 09 Jun 2026 14:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-459
CWE-724

Tue, 09 Jun 2026 12:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: tun: free page on build_skb failure in tun_xdp_one() When build_skb() fails in tun_xdp_one(), the function sets ret to -ENOMEM and jumps to the out label, which returns without freeing the page that vhost_net_build_xdp() allocated for the frame. As with the short-frame rejection path, tun_sendmsg() discards the per-buffer error and still returns total_len, so vhost_tx_batch() takes the success path and never frees the page. Each build_skb() failure in a batch leaks one page-frag chunk. Free the page before taking the error path, matching the put_page() the other error exits of tun_xdp_one() already perform.
Title tun: free page on build_skb failure in tun_xdp_one()
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-06-19T12:00:24.388Z

Reserved: 2026-05-13T15:03:33.112Z

Link: CVE-2026-46322

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-06-09T13:16:37.603

Modified: 2026-06-14T06:16:24.780

Link: CVE-2026-46322

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-06-09T00:00:00Z

Links: CVE-2026-46322 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-06-14T07:00:17Z

Weaknesses
  • CWE-772

    Missing Release of Resource after Effective Lifetime