CVE-2026-46300
Description
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: preserve shared-frag marker during coalescing skb_try_coalesce() can attach paged frags from @from to @to. If @from has SKBFL_SHARED_FRAG set, the resulting @to skb can contain the same externally-owned or page-cache-backed frags, but the shared-frag marker is currently lost. That breaks the invariant relied on by later in-place writers. In particular, ESP input checks skb_has_shared_frag() before deciding whether an uncloned nonlinear skb can skip skb_cow_data(). If TCP receive coalescing has moved shared frags into an unmarked skb, ESP can see skb_has_shared_frag() as false and decrypt in place over page-cache backed frags. Propagate SKBFL_SHARED_FRAG when skb_try_coalesce() transfers paged frags. The tailroom copy path does not need the marker because it copies bytes into @to's linear data rather than transferring frag descriptors.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
Linux Kernel - Local Privilege Escalation
OS impact
Linux kernel Affected 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 7.1 | Affected | — |
| — | Affected | 5.15.208 |
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Windows Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
AlmaLinux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | kernel-64k-debug-devel-5.14.0-611.54.6.el9_7.aarch64.rpm |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.12.90-1 |
| sid | Fixed | 7.0.9-1 |
| forky | Fixed | 7.0.9-1 |
| bullseye | Fixed | 5.10.257-1 |
| bookworm | Fixed | 6.1.174-1 |
Red Hat Fixed 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | — |
| 8 | Fixed | — |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| aws | aws | | |
References
- https://access.redhat.com/errata/RHSA-2026:19568
- https://git.kernel.org/stable/c/2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c
- https://git.kernel.org/stable/c/3599e6b3cc1ada96883d496a50a210d3afbb6987
- https://git.kernel.org/stable/c/3884358a9286b17f389a72b1426fc4547c23c111
- https://git.kernel.org/stable/c/3bd9e113d50034db99d7ef69fd8e5242d15e414a
- https://git.kernel.org/stable/c/760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e
- https://git.kernel.org/stable/c/78bf6b6bb19541d19fbda6242e7cfe2c682763c0
- https://git.kernel.org/stable/c/9d3e5fd19fe1063bf607219e8562fbd567b8e8d5
- https://git.kernel.org/stable/c/f84eca5817390257cef78013d0112481c503b4a3
- http://www.openwall.com/lists/oss-security/2026/05/13/5
- http://www.openwall.com/lists/oss-security/2026/05/21/11
- http://www.openwall.com/lists/oss-security/2026/05/21/12
- http://www.openwall.com/lists/oss-security/2026/05/21/13
- https://www.suse.com/security/cve/CVE-2026-46300.html
- https://security-tracker.debian.org/tracker/CVE-2026-46300
- https://access.redhat.com/errata/RHSA-2026:19666
- https://bugzilla.redhat.com/2477015
- https://bugzilla.redhat.com/2477802
- https://errata.almalinux.org/8/ALSA-2026-19666.html
- https://bugzilla.redhat.com/show_bug.cgi?id=2477015
- https://bugzilla.redhat.com/show_bug.cgi?id=2477802
- https://errata.almalinux.org/8/ALSA-2026-A008.html
- https://access.redhat.com/errata/RHSA-2026:19664
- https://errata.almalinux.org/8/ALSA-2026-19664.html
- https://errata.almalinux.org/9/ALSA-2026-A009.html
CWEs
CWE-787
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.