Executive brief
A vulnerability in the Linux kernel's Ceph network storage client could allow a remote attacker to cause a system crash. The issue occurs during the authentication process when errors are not properly handled, leading to a system failure. This affects systems using Ceph for distributed storage, including certain industrial control components from Siemens.
Technical details
A NULL pointer dereference vulnerability exists in the libceph module of the Linux kernel due to improper error handling in mon_handle_auth_done(). When ceph_auth_handle_reply_done() returns an error, mon_handle_auth_done() fails to propagate this error, allowing the msgr2 protocol to attempt session establishment in the background. In secure mode, this inconsistency triggers a warning in setup_crypto() and subsequently leads to a NULL pointer dereference in prepare_auth_signature(). This can be exploited by a network-reachable attacker to cause a denial of service (kernel panic). Patches have been released for various stable kernel branches.
Affected products
- Linux Linux Kernel cd1a677cad99 to 77229551f2cf72f3e35636db68e6a825b912cf16
- Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP V3.1.6
- Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP V3.1.6
- Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP V3.1.6
Timeline
- 2026-01-23: advisory: Initial NVD publication
- 2026-01-17: patched: Fix committed to stable kernel trees
- 2026-07-14: other: Siemens advisory added to record
References
- https://git.kernel.org/stable/c/33908769248b38a5e77cf9292817bb28e641992d
- https://git.kernel.org/stable/c/77229551f2cf72f3e35636db68e6a825b912cf16
- https://git.kernel.org/stable/c/9e0101e57534ef0e7578dd09608a6106736b82e5
- https://git.kernel.org/stable/c/d2c4a5f6996683f287f3851ef5412797042de7f1
- https://git.kernel.org/stable/c/e097cd858196b1914309e7e3d79b4fa79383754d
- https://git.kernel.org/stable/c/e84b48d31b5008932c0a0902982809fbaa1d3b70
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html