CVE-2026-68300
Published: August 12, 2026Last modified: August 14, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: sctp: auth: verify auth requirement when auth_chunk is NULL sctp_auth_chunk_verify() returns true unconditionally when chunk->auth_chunk is NULL, silently skipping authentication. This is incorrect when: 1. skb_clone() failed in the BH receive path, leaving auth_chunk NULL. In sctp_endpoint_bh_rcv() asoc is NULL for new connections, so the early sctp_auth_recv_cid() check cannot catch this. 2. No AUTH chunk precedes COOKIE-ECHO, so skb_clone() is never called and auth_chunk remains NULL. Fix by checking sctp_auth_recv_cid() when auth_chunk is NULL: if authentication is required, return false to drop the chunk; otherwise continue normally.
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 (6.1.177-r0) |
| 25 LTS | linux-lts | Fixed (6.12.103-r0) | |
| Stream | linux-lts | Fixed (6.18.43-r0) |
References
- https://git.kernel.org/stable/c/18957373920caf5cdaf5cf32e5d1d7a99ca7700a
- https://git.kernel.org/stable/c/28c5fdce9dd955d2baf5e28987819b6d7cfaf646
- https://git.kernel.org/stable/c/5a022ac51ad83b4ce6c898f4b9eefc65bd26b247
- https://git.kernel.org/stable/c/6caf0e8590c0bf05a76b0d387726adf3a6f3725c
- https://git.kernel.org/stable/c/83f5031f2a6a49d696eb4cc0898345d12f9c6451
- https://git.kernel.org/stable/c/8e04823c120b376ef7dab14b60ebf6823aa16c14
- https://git.kernel.org/stable/c/a129792b3aef15002746c13522781d92ed3522c3
- https://git.kernel.org/stable/c/ec2e157fc9678a9bc411305a25aec3fd337d7efb