Status: UPDATED | Advisory ID: CVE-2026-63992
| CVE | CVE-2026-63992 |
| CVSS Score / Version | 9.1 (Critical) / CVSS v3.1 |
| Updated | 2026-10-07 |
| CVSS Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
| CVSS Prose | attack vector is network; attack complexity is low; privileges required is none; user interaction is none; scope is unchanged; confidentiality impact is high; integrity impact is none; availability impact is high. |
| Affected products | Linux Kernel |
| Classified as | CWE-125 (Out-of-bounds Read) |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Linux | Linux Kernel |
| Subsystems | OT Supporting Infrastructure |
| Sectors | All Sectors |
In the Linux kernel, the following vulnerability has been resolved:
tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()
In some cases, iptunnel_pmtud_check_icmp() can be called while
skb transport header is not set.
This triggers an out-of-bound access, because
(typeof(skb->transport_header))~0U is 65535.
Access the icmp header based on IPv4 network header,
after making sure icmp->type is present in skb linear part.
Note that iptunnel_pmtud_check_icmpv6()) is fine. (NVD)
Monitor Linux's web page for any future patch releases.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-63992 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-63992 |