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.
https://www.securityweek.com/poc-released-for-dirtydecrypt-linux-kernel-vulnerability/
https://www.infosecurity-magazine.com/news/fragnesia-linux-kernel-lpe-root/
https://thehackernews.com/2026/05/new-fragnesia-linux-kernel-lpe-grants.html
https://docs.cloud.google.com/support/bulletins/index#gcp-2026-033
https://aws.amazon.com/security/security-bulletins/rss/2026-030-aws/
https://github.com/v12-security/pocs/tree/main/fragnesia
https://aws.amazon.com/security/security-bulletins/rss/2026-029-aws/
https://git.kernel.org/stable/c/f84eca5817390257cef78013d0112481c503b4a3
https://git.kernel.org/stable/c/9d3e5fd19fe1063bf607219e8562fbd567b8e8d5
https://git.kernel.org/stable/c/78bf6b6bb19541d19fbda6242e7cfe2c682763c0
https://git.kernel.org/stable/c/760e1addc27ba1a7beb4a0a7e8b3e9ec49e7a34e
https://git.kernel.org/stable/c/3bd9e113d50034db99d7ef69fd8e5242d15e414a
https://git.kernel.org/stable/c/3884358a9286b17f389a72b1426fc4547c23c111
https://git.kernel.org/stable/c/3599e6b3cc1ada96883d496a50a210d3afbb6987
https://git.kernel.org/stable/c/2f2b16022a2e10ca7bccfb98db5ed2ec0f72641c
http://www.openwall.com/lists/oss-security/2026/05/21/13
http://www.openwall.com/lists/oss-security/2026/05/21/12
Published: 2026-05-23
Updated: 2026-05-30
Named Vulnerability: Fragnesia
Base Score: 6.8
Vector: CVSS2#AV:L/AC:L/Au:S/C:C/I:C/A:C
Severity: Medium
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
EPSS: 0.00054
Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.
Vulnerability of Interest