CVE-2026-93105EPSS p5.2%
CVE-2026-93105CVE-2026-93105
Description
In the Linux kernel, the following vulnerability has been resolved:
esp: do not unref managed frag pages in esp_ssg_unref()
esp_ssg_unref() releases the page references held on the source
scatterlist after the AEAD operation completes. It calls
skb_page_unref() on every frag page for an out-of-place transform
(req->src != req->dst), and in the error path of esp_output_tail()
(already_unref == true) on the request's own scatterlist.
This is wrong when the skb carries managed frags
(SKBFL_MANAGED_FRAG_REFS). Managed frags are owned by a zerocopy ubuf
and the skb does not hold a per-frag page reference; io_uring SEND_ZC
with a registered buffer attaches the bvec pages this way via
io_sg_from_iter(). The rest of the stack honours this invariant:
skb_release_data() skips the per-frag unref when SKBFL_MANAGED_FRAG_REFS
is set, and skb_zcopy_managed() is the guard used at the other unref
sites.
esp_ssg_unref() is missing that guard, so for a managed-frag skb it
drops a page reference t
Scoring
| CVSS | 7.8 () |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 0.17% probability of exploitation · percentile 5.2% · 2026-10-06T12:00:23Z |
| Last modified | 2026-09-18 |