A AegiFlow
CRITICALCVSS 9.8

CVE-2026-68123

CVE-2026-68123 updated by NVD

Modified
2026-08-21
Sources
nvd

Summary

In the Linux kernel, the following vulnerability has been resolved: openvswitch: fix GSO userspace truncation underflow OVS_ACTION_ATTR_TRUNC currently stores a delta from the original skb length in OVS_CB(skb)->cutlen. When a later userspace action segments a GSO skb, queue_gso_packets() reuses that delta for each smaller segment. A segment can then reach queue_userspace_packet() with cutlen greater than skb->len, underflowing the length passed to skb_zerocopy(). Store the maximum preserved length instead and bound each consumer against the current skb length. Use U32_MAX as the no-truncation sentinel so the value remains valid if skb geometry changes before a consumer handles it.

References

Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.

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