CVE-2026-63994
Last modified
CVE-2026-63994 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.. EPSS estimates a 0.51% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.
Metrics
Weakness Enumeration
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 5.9, < 5.10.259 | — |
| Linux | Linux Kernel | >= 5.11, < 5.15.210 | — |
| Linux | Linux Kernel | >= 5.16, < 6.1.176 | — |
| Linux | Linux Kernel | >= 6.2, < 6.6.143 | — |
| Linux | Linux Kernel | >= 6.7, < 6.12.93 | — |
| Linux | Linux Kernel | >= 6.13, < 6.18.35 | — |
| Linux | Linux Kernel | >= 6.19, < 7.0.12 | — |
| Linux | Linux Kernel | 7.1 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
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