CVE-2026-46300: Linux kernel · net: skbuff: preserve shared-frag marker during coalescing
Affects Linux kernelSource GCVE Database
Exploited in the wild · KEV due 31 Oct 2026 · public exploit available (Metasploit, Exploit-DB) · fixed in f84eca5817390257cef78013d0112481c503b4a3 : patch Linux kernel now.
Data as of 28 Oct 2026, 22:27 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
- Patch
- Available – fixed in f84eca5817390257cef78013d0112481c503b4a3, 3884358a9286b17f389a72b1426fc4547c23c111, 3599e6b3cc1ada96883d496a50a210d3afbb6987 +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 23 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
1 Metasploit module · 1 Exploit-DB entry, 6 days after disclosure
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 158 days after disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by kernel.org
, 10 days before disclosure
CVE published
on cve.org
, t = 0
First Exploit-DB entry (opens in a new tab)
Linux Kernel - Local Privilege Escalation
, 6 days after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, 158 days after disclosure
KEV remediation due
US federal deadline
, 161 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- access.redhat.com/errata/RHSA-2026:23468 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23469 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23470 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23471 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:24814 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:25044 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28887 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:33486 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34098 (opens in a new tab)
- access.redhat.com/errata/RHBA-2026:20032 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:19521 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:19540 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
Description
CVE-2026-46300 is a vulnerability in the Linux kernel's network stack where the skb_try_coalesce() function fails to preserve the shared-frag marker during coalescing of socket buffers. This flaw can cause the loss of the SKBFL_SHARED_FRAG flag, which is critical for later in-place writers such as ESP input processing. As a result, ESP may incorrectly decrypt data in place over page-cache-backed fragments, potentially leading to local privilege escalation. The issue has been addressed by propagating the shared-frag marker correctly during coalescing. A patch is available from Red Hat for kernel version 5.14.0-570 and related updates.
References
- nvd.nist.gov/vuln/detail/CVE-2026-46300 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23468 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23469 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23470 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:23471 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:24814 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:25044 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:28887 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:33486 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:34098 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-46300 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2477015 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
- git.kernel.org/stable/c/2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c (opens in a new tab)
- git.kernel.org/stable/c/3599e6b3cc1ada96883d496a50a210d3afbb6987 (opens in a new tab)
- git.kernel.org/stable/c/3884358a9286b17f389a72b1426fc4547c23c111 (opens in a new tab)
- git.kernel.org/stable/c/3bd9e113d50034db99d7ef69fd8e5242d15e414a (opens in a new tab)
- git.kernel.org/stable/c/760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e (opens in a new tab)
- git.kernel.org/stable/c/78bf6b6bb19541d19fbda6242e7cfe2c682763c0 (opens in a new tab)