CVE-2026-74473
Published: August 18, 2026Last modified: August 18, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: vxlan: use pskb_network_may_pull() in route_shortcircuit() route_shortcircuit() currently calls pskb_may_pull(skb, sizeof(struct iphdr)) (or ipv6hdr), which checks if bytes are available starting from skb->data. However, in vxlan_xmit(), skb->data points to the MAC header, so skb_network_offset(skb) is ETH_HLEN (14 bytes). Using pskb_may_pull(skb, 20) only checks 20 bytes from skb->data (which is 14 bytes MAC header + 6 bytes of IP header), leaving the rest of the IP header potentially un-pulled in non-linear frags. Subsequent dereferences of ip_hdr(skb)->daddr can read beyond the pulled linear buffer length. Fix this by using pskb_network_may_pull(), which adds skb_network_offset(skb) to the length check to ensure the full network header is present in the linear buffer.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 9.8 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Vulnerable (6.1.182-r0) |
| 25 LTS | linux-lts | Fixed (6.12.103-r0) | |
| Stream | linux-lts | Vulnerable (6.18.43-r0) |
References
- https://git.kernel.org/stable/c/26bb2dd0a8839617e2c79ffbbe1923f8e4bab9fb
- https://git.kernel.org/stable/c/42887be7c4cf283cce02cd0fb6411221167c8b6c
- https://git.kernel.org/stable/c/4f3f96e771a20263635bb5e1307c112d613b4bbd
- https://git.kernel.org/stable/c/aa0d31376d574ac858a40078431a77127bf04ee4
- https://git.kernel.org/stable/c/ee799977d7941dbfb11049e17edd9eaf4f8820f7