CVE Catalog

CVE-2026-46323

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.14%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel, a vulnerability in the GRO (Generic Receive Offload) mechanism allows merging zerocopy packets without checking the SKBFL_MANAGED_FRAG_REFS flag, potentially leading to use-after-free (UAF). The issue occurs when either the last packet in the GRO chain or the source packet is zerocopy.

Risk Assessment

The risk includes potential privilege escalation or system crash (kernel panic) due to use-after-free, which could be exploited by a local attacker to destabilize the system.

Recommendation

Immediately update the Linux kernel to a version containing the fix that prevents merging zerocopy packets in GRO.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS