Disclosure summary
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.
Source-reported weakness categories
CWE-125
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2026-63992
Open original source · Updated Oct 07, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
| Vendor | Product / association | Version / bounds |
|---|---|---|
| linux | linux_kernel | * {"versionStartIncluding":"6.19","versionEndExcluding":"7.0.12"} |
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | 7.1 |
| linux | linux_kernel | 7.1 |
Original records & references
- NIST NVD record
- CVE Program record
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
- git.kernel.org — Patch
PUBLISHED 2026-07-19T12:17:38-04:00
MODIFIED 2026-10-07T16:29:43-04:00
INGESTED 2026-10-10T20:25:11-04:00