CVE-2026-63993
In the Linux kernel, the following vulnerability has been resolved:
vxlan: do not reuse cached iphdr() value after skbtunnelcheckpmtu()
skbtunnelcheck_pmtu() can change skb->head.
Reusing oldiph afer skbtunnelcheckpmtu() can cause an UAF.
Use instead ip_hdr(skb) as done in drivers/net/bareudp.c
and drivers/net/geneve.c.
Found by Sashiko.
Package Versions Affected
Automatically patch vulnerabilities without upgrading
CVSS Version



Related Resources
References
https://git.kernel.org/stable/c/5303925e360527243b46a440a04667826bbc72b7, https://git.kernel.org/stable/c/609e63312c29aad18026a1d3222e123d4b6b0feb, https://git.kernel.org/stable/c/6b8bfce9d2f774d2c2243e0248e03efb99bba6c0, https://git.kernel.org/stable/c/7d9ef0cb271555d8cf39fefe6c981e1493b25ecf, https://git.kernel.org/stable/c/8d435d68d71fb875876b722f4136caf74f2f48bd, https://git.kernel.org/stable/c/9257f56ac47ef1976bcd056cf986a9988eeec67a, https://git.kernel.org/stable/c/a493efd4336cf19122ae0e4cbb3d31b32d70deea, https://git.kernel.org/stable/c/dc3bfa050f873371e745bdf478b1f5b738e5733d, https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63993.json, https://nvd.nist.gov/vuln/detail/CVE-2026-63993, https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git