Description
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.
Affected products
linux: linux kernel
References7
- git.kernel.org/stable/c/016bc663657366d386993f63eb31072eb45a2b77 Patch
- git.kernel.org/stable/c/4b2738b93edad661178340239de657d876b73d3d Patch
- git.kernel.org/stable/c/5199c125d25aeae8615c4fc31652cc0fe624338e Patch
- git.kernel.org/stable/c/8f2be7285941a33a9f72579a23b96392f83c758e Patch
- git.kernel.org/stable/c/927e4bd5692f2a4901808822981fb2c8d4456548 Patch
- git.kernel.org/stable/c/9ded62c302c0342efdb5eda3bf6e75720caad0df Patch
- git.kernel.org/stable/c/f101271fcf55d7eacfefd610b51ec65f46ba8118 Patch
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 43 · as of 14 November 2026
- CWE
- CWE-476
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