High 7.5Published May 27, 2026

CVE-2026-46024libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply()

Updated under an hour ago (Oct 27, 2026, 4:30 AM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: libceph: Prevent potential null-ptr-deref in ceph_handle_auth_reply() If a message of type CEPH_MSG_AUTH_REPLY contains a zero value for both protocol and result, this is currently not treated as an error. In case of ac->negotiating == true and ac->protocol > 0, this leads to setting ac->protocol = 0 and ac->ops = NULL. Thereafter, the check for ac->protocol != protocol returns false, and init_protocol() is not called. Subsequently, ac->ops->handle_reply() is called, which leads to a null pointer dereference, because ac->ops is still NULL. This patch changes the check for ac->protocol != protocol to !ac->protocol, as this also includes the case when the protocol was set to zero in the message. This causes the message to be treated as containing a bad auth protocol.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-476
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before 9ded62c302c0342efdb5eda3bf6e75720caad0df; from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before f101271fcf55d7eacfefd610b51ec65f46ba8118; 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc builds before 4b2738b93edad661178340239de657d876b73d3d; from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before 927e4bd5692f2a4901808822981fb2c8d4456548; from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before 016bc663657366d386993f63eb31072eb45a2b77; from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before 8f2be7285941a33a9f72579a23b96392f83c758e; from 4e7a5dcd1bbab6560fbc8ada29a840e7a20ed7bc before 5199c125d25aeae8615c4fc31652cc0fe624338e	CNA record
linux linux_kernel linux:linux_kernel	from 2.6.34.1 before 5.15.209; from 5.16 before 6.1.175; from 6.2 before 6.6.140; from 6.7 before 6.12.86; from 6.13 before 6.18.27; from 6.19 before 7.0.4; 2.6.34; 2.6.34; and 5 more ranges	NVD

References

References

https://git.kernel.org/stable/c/9ded62c302c0342efdb5eda3bf6e75720caad0df	patch
https://git.kernel.org/stable/c/f101271fcf55d7eacfefd610b51ec65f46ba8118	patch
https://git.kernel.org/stable/c/4b2738b93edad661178340239de657d876b73d3d	patch
https://git.kernel.org/stable/c/927e4bd5692f2a4901808822981fb2c8d4456548	patch
https://git.kernel.org/stable/c/016bc663657366d386993f63eb31072eb45a2b77	patch
https://git.kernel.org/stable/c/8f2be7285941a33a9f72579a23b96392f83c758e	patch
https://git.kernel.org/stable/c/5199c125d25aeae8615c4fc31652cc0fe624338e	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.