CVE-2026-80924: crypto: krb5 - use kfree_sensitive() for derived key buffers

CVE-2026-80924: crypto: krb5 - use kfree_sensitive() for derived key buffers

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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

crypto: krb5 - use kfree_sensitive() for derived key buffers

crypto_krb5_prepare_encryption() and crypto_krb5_prepare_checksum()
free the buffer holding the freshly derived keys with plain kfree(),
leaving the key material behind in the freed slab object.

The Linux kernel CVE team has assigned CVE-2026-80924 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 6.15 with commit 3936f02bf2d3308a7359dd37dd96cd60603d8170 and fixed in 6.18.49 with commit 731a5b6fb4c1705f9405d9029dd64ea81e336207
	Issue introduced in 6.15 with commit 3936f02bf2d3308a7359dd37dd96cd60603d8170 and fixed in 7.1.13 with commit 91b96dc9cc250cd16751f53de525cf3442ca0962
	Issue introduced in 6.15 with commit 3936f02bf2d3308a7359dd37dd96cd60603d8170 and fixed in 7.2.3 with commit a1bf79365794783b19f5b09e8a23f7ee311e8931
	Issue introduced in 6.15 with commit 3936f02bf2d3308a7359dd37dd96cd60603d8170 and fixed in 7.3-rc1 with commit f7d53dd3f267e46a784f219a75072f2f400d42b9

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-80924
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	crypto/krb5/krb5_api.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/731a5b6fb4c1705f9405d9029dd64ea81e336207
	https://git.kernel.org/stable/c/91b96dc9cc250cd16751f53de525cf3442ca0962
	https://git.kernel.org/stable/c/a1bf79365794783b19f5b09e8a23f7ee311e8931
	https://git.kernel.org/stable/c/f7d53dd3f267e46a784f219a75072f2f400d42b9