by Kastro CVE-2026-63992
Linux Linux — tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()
Description · from the CVE record
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
ProductAffectedFixed inSource
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < 5a92cb45e34749865d03daf8d3500f77b5f6644c5a92cb45e34749865d03daf8d3500f77b5f6644cCNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < c7b7ec3e69e673c0d6b57f74d21da50c485c598ec7b7ec3e69e673c0d6b57f74d21da50c485c598eCNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < 7f4f7efe7f30edd29c4988de01728bf2398217e47f4f7efe7f30edd29c4988de01728bf2398217e4CNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < e917d0c69f01af2bb4fbea2b66d560a53b3ac7ece917d0c69f01af2bb4fbea2b66d560a53b3ac7ecCNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < a096b6e34f602950af9a2b0856cd93a5f4c276d7a096b6e34f602950af9a2b0856cd93a5f4c276d7CNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < 43368636c663cff6e59dde93cf4b8e43ac28eb9343368636c663cff6e59dde93cf4b8e43ac28eb93CNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < cb549df9ce4ee15c9d5b19ddab12cf2128e4313ccb549df9ce4ee15c9d5b19ddab12cf2128e4313cCNA
Linux4cb47a8644cc9eb8ec81190a50e79e6530d0297f – < 509323077ef79a26ba0c60bb556e45c12c398b2d509323077ef79a26ba0c60bb556e45c12c398b2dCNA
Linux5.95.10.259CNA
Scores by source
Linux (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: partial