CVE-2026-68123
In the Linux kernel, the following vulnerability has been resolved:
openvswitch: fix GSO userspace truncation underflow
OVSACTIONATTR_TRUNC currently stores a delta from the original skb
length in OVS_CB(skb)->cutlen. When a later userspace action segments a
GSO skb, queuegsopackets() reuses that delta for each smaller segment.
A segment can then reach queueuserspacepacket() 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.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
References
https://git.kernel.org/stable/c/100a23b1613e9218e0af654ef102352c713f0263, https://git.kernel.org/stable/c/2623c48cc3a8da9a1886fd8f65c0e348f4406fd6, https://git.kernel.org/stable/c/4032f8ed10fcb84d41c508dfb04be96589f78dfe, https://git.kernel.org/stable/c/50a6a85f3d6b1d22d8436848606cdef5d2c490b4, https://git.kernel.org/stable/c/a16eaaf7c0b0ccdef6166707d90ffbc6eebf6855, https://git.kernel.org/stable/c/e211b081901ffca76674082c73eeaed53524c369, https://git.kernel.org/stable/c/ea85dbcbe8d4056ecb54352f97743d138ea4c407, https://git.kernel.org/stable/c/fbfa3ad2ad6f3a5624aba5211c46290fb98cc9dc, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68123.json, https://nvd.nist.gov/vuln/detail/CVE-2026-68123, https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git