PT-2026-39081 · Ceph+1 · Ceph+1

Published 2026-05-08 · Updated 2026-05-08 · CVE-2026-43420

Positive Technologies (AI Summary)

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the Ceph component of the Linux kernel where an i nlink counter underrun can occur during an asynchronous unlink operation. In the ceph unlink() function, a request is submitted to the Metadata Server (MDS) via ceph mdsc submit request() without waiting for completion. A race condition occurs if a worker thread processes a reply or capability operation (such as CEPH CAP OP IMPORT or CEPH CAP OP GRANT) and calls set nlink() to update the i nlink counter to zero before the original ceph unlink() process calls drop nlink(). This results in an illegal decrement of a zero-value counter, triggering a system warning.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Related Identifiers

CVE-2026-43420

Affected Products

Ceph

Linux Kernel

References · 10

• https://nvd.nist.gov/vuln/detail/CVE-2026-43420 · Security Note
• https://git.kernel.org/stable/c/aedd29386b23f3e1e6818943e11abfff2953732f · Note
• https://twitter.com/CVEnew/status/2052767654478520740 · Twitter Post
• https://git.kernel.org/stable/c/6d5fd8bb574bef039eb3b738e523870433a2aeb9 · Note
• https://git.kernel.org/stable/c/8975b85b0d45ca811ace6fac5907652f2310e5ac · Note
• https://git.kernel.org/stable/c/7db008e85a5d17b64bc5390b828bf457ae91a415 · Note
• https://git.kernel.org/stable/c/ce0123cbb4a40a2f1bbb815f292b26e96088639f · Note
• https://git.kernel.org/stable/c/fcc477a6e8856c8a42b3c9e171724d8d6dfadd06 · Note
• https://git.kernel.org/stable/c/b3f5513141ecc6b277a8f7b7efe58a0cf9a5e859 · Note
• https://git.kernel.org/stable/c/9b31e88ac5623d15c8bc46f69dfe1d3b43a8f67c · Note