CVE-2026-63994
Description
In the Linux kernel, the following vulnerability has been resolved:
tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]()
Sashiko found that iptunnel_pmtud_build_icmp() and
iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr()
before an skb_cow() call which can reallocate skb->head.
Fix this possible UAF by initializing the local variables
after the skb_cow() call.
Remove skb_reset_network_header() calls which were not needed.
Metadata
Severity & Metrics
No CVSS data available.
Affected products (2)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| Linux | Linux | — | 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 95b6d772bfe788331d9742d73eaa12e113b2adc4, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 7254aef4d1a7e18e887af9010e2f2dc34806789b, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < bf8b3f34c37c162357138e7c0942723b8b94fed1, 4cb47a8644cc9eb8ec81190a50e79e6530d0297f < 76cd9398a0470257ab765bdf5f358a2af2e17934 … |
| Linux | Linux | — | 5.9, 0 < 5.9, 5.10.259 ≤ 5.10.*, 5.15.210 ≤ 5.15.* … |
References (8)
- https://git.kernel.org/stable/c/95b6d772bfe788331d9742d73eaa12e113b2adc4
- https://git.kernel.org/stable/c/7254aef4d1a7e18e887af9010e2f2dc34806789b
- https://git.kernel.org/stable/c/bf8b3f34c37c162357138e7c0942723b8b94fed1
- https://git.kernel.org/stable/c/76cd9398a0470257ab765bdf5f358a2af2e17934
- https://git.kernel.org/stable/c/50750d86a2e5266aba0c295483b3397843198b11
- https://git.kernel.org/stable/c/6dff77899b9e9fe5d854abda3a98ad04e7229ef7
- https://git.kernel.org/stable/c/f3f204541f280a6ecb04503a0d6794d93990ca43
- https://git.kernel.org/stable/c/b4bc94353050b1fa7b702bd4c6600710dd926cff