CVE-2026-89528 svcrdma: Reject Read lists that exceed the page budget
A remote attacker can cause a kernel crash by sending crafted RDMA Read requests that bypass page budget checks, leading to a NULL pointer dereference.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-89528?
CVE-2026-89528 is a high-severity vulnerability in Linux, published on 11 Sep 2026. 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:
svcrdma: Reject Read lists that exceed the page budget
Individual Read segment lengths are validated at decode time, but nothing prevents a requester from sending multiple segments whose cumulative length exceeds the rq_pages array budget. When one segment fills the page array exactly, the runtime guard in svc_rdma_build_read_segment() is bypassed because len reaches zero. A subsequent segment then accesses the NULL sentinel slot at rq_pages[rq_maxpages], resulting in a NULL pointer dereference during DMA mapping.
Accumulate pages across all Read segments and reject the message at decode time when the total would overflow the page budget.
Which versions are affected by CVE-2026-89528?
How do I fix CVE-2026-89528?
Apply the vendor's patch.
Is CVE-2026-89528 being exploited?
There is no known exploitation of CVE-2026-89528 in the wild and no public exploit code.
Sources
Also known as AZL-100166, BELL-CVE-2026-89528, DEBIAN-CVE-2026-89528, GHSA-4rjj-pgm8-m2r9, UBUNTU-CVE-2026-89528.