cbcvebase.
CVE-2026-63992
published 2026-07-19

CVE-2026-63992: In the Linux kernel, the following vulnerability has been resolved: tunnels: do not assume transport header in iptunnel_pmtud_check_icmp() In some cases…

PriorityP350critical9.1CVSS 3.1
AVNACLPRNUINSUCHINAH
EPSS
0.51%
42.2th percentile
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.

Affected

67 ranges· showing 25
VendorProductVersion rangeFixed in
linuxlinux——
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 5a92cb45e34749865d03daf8d3500f77b5f6644c5a92cb45e34749865d03daf8d3500f77b5f6644c
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < c7b7ec3e69e673c0d6b57f74d21da50c485c598ec7b7ec3e69e673c0d6b57f74d21da50c485c598e
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 7f4f7efe7f30edd29c4988de01728bf2398217e47f4f7efe7f30edd29c4988de01728bf2398217e4
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < e917d0c69f01af2bb4fbea2b66d560a53b3ac7ece917d0c69f01af2bb4fbea2b66d560a53b3ac7ec
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < a096b6e34f602950af9a2b0856cd93a5f4c276d7a096b6e34f602950af9a2b0856cd93a5f4c276d7
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 43368636c663cff6e59dde93cf4b8e43ac28eb9343368636c663cff6e59dde93cf4b8e43ac28eb93
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < cb549df9ce4ee15c9d5b19ddab12cf2128e4313ccb549df9ce4ee15c9d5b19ddab12cf2128e4313c
linuxlinux>= 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 509323077ef79a26ba0c60bb556e45c12c398b2d509323077ef79a26ba0c60bb556e45c12c398b2d
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel>= 5.11 < 5.15.2105.15.210
linuxlinux_kernel>= 5.16 < 6.1.1766.1.176
linuxlinux_kernel>= 5.9 < 5.10.2595.10.259
linuxlinux_kernel>= 6.13 < 6.18.356.18.35
linuxlinux_kernel>= 6.19 < 7.0.127.0.12
linuxlinux_kernel>= 6.2 < 6.6.1436.6.143
linuxlinux_kernel>= 6.7 < 6.12.936.12.93
ubuntulinux——
ubuntulinux-aws——
ubuntulinux-aws-6.8——

CVSS provenance

nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
vendor_ubuntu9.4CRITICAL
vendor_redhat9.1CRITICAL
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