CVE-2026-23285 drbd: fix null-pointer dereference on local read error

What is CVE-2026-23285?

CVE-2026-23285 is a medium-severity vulnerability in Linux kernel, published on 25 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

drbd: fix null-pointer dereference on local read error

In drbd_request_endio(), READ_COMPLETED_WITH_ERROR is passed to __req_mod() with a NULL peer_device:

__req_mod(req, what, NULL, &m);

The READ_COMPLETED_WITH_ERROR handler then unconditionally passes this NULL peer_device to drbd_set_out_of_sync(), which dereferences it, causing a null-pointer dereference.

Fix this by obtaining the peer_device via first_peer_device(device), matching how drbd_req_destroy() handles the same situation.

Weakness: CWE-476

Which versions are affected by CVE-2026-23285?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-23285?

Apply the vendor's patch.

Is CVE-2026-23285 being exploited?

There is no known exploitation of CVE-2026-23285 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-80580, BELL-CVE-2026-23285, DEBIAN-CVE-2026-23285, GHSA-h6wj-6663-2gvh, ROOT-OS-DEBIAN-13-CVE-2026-23285, ROOT-OS-UBUNTU-2204-CVE-2026-23285 and 2 more.