CVE-2026-63993
Full vulnerability record from the local CVENow database.
Description
In the Linux kernel, the following vulnerability has been resolved: vxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu() skb_tunnel_check_pmtu() can change skb->head. Reusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF. Use instead ip_hdr(skb) as done in drivers/net/bareudp.c and drivers/net/geneve.c. Found by Sashiko.
Severity
CRITICAL
CVSS score
9.8
(v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-19 16:17:38.823000
Last modified
2026-10-19 21:17:17.160000
View original CVE JSON
{
"id": "CVE-2026-63993",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2026-07-19T16:17:38.823",
"lastModified": "2026-10-19T21:17:17.160",
"vulnStatus": "Modified",
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: do not reuse cached ip_hdr() value after skb_tunnel_check_pmtu()\n\nskb_tunnel_check_pmtu() can change skb->head.\n\nReusing old_iph afer skb_tunnel_check_pmtu() can cause an UAF.\n\nUse instead ip_hdr(skb) as done in drivers/net/bareudp.c\nand drivers/net/geneve.c.\n\nFound by Sashiko."
}
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