CVE-2026-63992

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Source
https://cve.org/CVERecord?id=CVE-2026-63992
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63992.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-63992
Downstream
Published
2026-07-19T14:56:12.528Z
Modified
2026-07-22T05:29:59.708125709Z
Severity
  • 9.1 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H CVSS Calculator
Summary
tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()
Details

In the Linux kernel, the following vulnerability has been resolved:

tunnels: do not assume transport header in iptunnelpmtudcheck_icmp()

In some cases, iptunnelpmtudcheck_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 iptunnelpmtudcheck_icmpv6()) is fine.

Database specific 
{
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63992.json"
}
References

Affected packages

Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Affected ranges

Type
GIT
Repo
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Events
Introduced
4cb47a8644cc9eb8ec81190a50e79e6530d0297f
Fixed
5a92cb45e34749865d03daf8d3500f77b5f6644c
Fixed
c7b7ec3e69e673c0d6b57f74d21da50c485c598e
Fixed
7f4f7efe7f30edd29c4988de01728bf2398217e4
Fixed
e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec
Fixed
a096b6e34f602950af9a2b0856cd93a5f4c276d7
Fixed
43368636c663cff6e59dde93cf4b8e43ac28eb93
Fixed
cb549df9ce4ee15c9d5b19ddab12cf2128e4313c
Fixed
509323077ef79a26ba0c60bb556e45c12c398b2d

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63992.json"

Linux / Kernel

Package

Name
Kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
5.9.0
Fixed
5.10.259
Type
ECOSYSTEM
Events
Introduced
5.11.0
Fixed
5.15.210
Type
ECOSYSTEM
Events
Introduced
5.16.0
Fixed
6.1.176
Type
ECOSYSTEM
Events
Introduced
6.2.0
Fixed
6.6.143
Type
ECOSYSTEM
Events
Introduced
6.7.0
Fixed
6.12.93
Type
ECOSYSTEM
Events
Introduced
6.13.0
Fixed
6.18.35
Type
ECOSYSTEM
Events
Introduced
6.19.0
Fixed
7.0.12

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63992.json"