CVE-2025-40187 net/sctp: fix a null dereference in sctp_disposition sctp_sf_do_5_1D_ce()
A null pointer dereference in the Linux kernel SCTP implementation allows attackers to cause a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-40187?
CVE-2025-40187 is a high-severity vulnerability in Linux, published on 12 Nov 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
net/sctp: fix a null dereference in sctp_disposition sctp_sf_do_5_1D_ce()
If new_asoc->peer.adaptation_ind=0 and sctp_ulpevent_make_authkey=0 and sctp_ulpevent_make_authkey() returns 0, then the variable ai_ev remains zero and the zero will be dereferenced in the sctp_ulpevent_free() function.
Which versions are affected by CVE-2025-40187?
How do I fix CVE-2025-40187?
Apply the vendor's patch.
Is CVE-2025-40187 being exploited?
There is no known exploitation of CVE-2025-40187 in the wild and no public exploit code.
Sources
Also known as AZL-70079, BELL-CVE-2025-40187, DEBIAN-CVE-2025-40187, GHSA-xp33-mgvv-9242, ROOT-OS-DEBIAN-11-CVE-2025-40187, ROOT-OS-DEBIAN-13-CVE-2025-40187 and 2 more.