CVE-2026-46323
Summary
In the Linux kernel, the following vulnerability has been resolved: net: gro: don't merge zcopy skbs skb_gro_receive() can currently copy frags between the source and GRO skb, without checking the zerocopy status, and in particular the SKBFL_MANAGED_FRAG_REFS flag. When SKBFL_MANAGED_FRAG_REFS is set, the skb doesn't hold a reference on the pages in shinfo->frags. Appending those frags to another skb's frags without fixing up the page refcount can lead to UAF. When either the last skb in the GRO chain (the one we would append frags to) or the source skb is zerocopy, don't merge the skbs.
Impact & exploitability
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products we track (1)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Official patch: https://git.kernel.org/stable/c/1f9c828556416fbe3f49386708ce999fc4d4da06 ↗
Additional information
- NVD record
- https://git.kernel.org/stable/c/1f9c828556416fbe3f49386708ce999fc4d4da06Patch
- https://git.kernel.org/stable/c/3c6cc9f2ca65b6dd61b1af75452dc0e1cd0aad8dPatch
- https://git.kernel.org/stable/c/44bea2032af0425e4ce6d26a8af0ede79db49ec1Patch
- https://git.kernel.org/stable/c/479084ae0e1d9cb7929cb4298d35623de189f80aPatch
- https://git.kernel.org/stable/c/4db79a322db8c97f7b73b8a347395ef4d685eb40Patch
- https://git.kernel.org/stable/c/e334cbf3388fd9334503a778a82d9e9f14dd2f71Patch
- https://access.redhat.com/errata/RHSA-2026:27708Advisory
- https://access.redhat.com/errata/RHSA-2026:27731Advisory