FreeBSD Errata Notice FreeBSD-EN-21:17.libradius
1 June, 2021 by errata-notices@freebsd.org | freebsd
FreeBSD-EN-21:17.libradius Errata Notice
The FreeBSD Project
Topic: Incorrect validation in rad_get_attr(3)
Category: core
Module: libradius
Announced: 2021-06-01
Affects: All supported versions of FreeBSD.
Corrected: 2021-05-28 17:00:19 UTC (stable/13, 13.0-STABLE)
2021-06-01 20:26:32 UTC (releng/13.0, 13.0-RELEASE-p2)
2021-05-28 17:03:20 UTC (stable/12, 12.2-STABLE)
2021-06-01 20:38:39 UTC (releng/12.2, 12.2-RELEASE-p8)
2021-05-28 17:02:43 UTC (stable/11, 11.4-STABLE)
2021-05-28 20:37:54 UTC (releng/11.4, 11.4-RELEASE-p11)
For general information regarding FreeBSD Errata Notices and Security
Advisories, including descriptions of the fields above, security
branches, and the following sections, please visit
<URL:https://security.FreeBSD.org/>.
I. Background
libradius(3) is a client and server library implementing the Remote
Authentication Dial In User Service (RADIUS) protocol. It is used by
pam_radius(8) and mpd5 (available in the ports tree as net/mpd5).
II. Problem Description
The patch for FreeBSD-SA-21:12.libradius modified rad_get_attr(3) to
verify that an attribute length smaller than the minimum required for
the attribute type and length fields is disallowed. This check may fail
incorrectly for the final attribute in a RADIUS message.
III. Impact
The bug may cause request validation to fail when it should succeed.
This can result in errors in applications making using of libradius(3).
IV. Workaround
No workaround is available. Systems not using libradius(3) are unaffected.
V. Solution
Upgrade your system to a supported FreeBSD stable or release / security
branch (releng) dated after the correction date.
Perform one of the following:
1) To update your system via a binary patch:
Systems running a RELEASE version of FreeBSD on the amd64, i386, or
(on FreeBSD 13 and later) arm64 platforms can be updated via the
freebsd-update(8) utility:
# freebsd-update fetch
# freebsd-update install
2) To update your system via a source code patch:
The following patches have been verified to apply to the applicable
FreeBSD release branches.
a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.
# fetch https://security.FreeBSD.org/patches/EN-21:17/libradius.patch
# fetch https://security.FreeBSD.org/patches/EN-21:17/libradius.patch.asc
# gpg --verify libradius.patch.asc
b) Apply the patch. Execute the following commands as root:
# cd /usr/src
# patch < /path/to/patch
c) Recompile the operating system using buildworld and installworld as
described in <URL:https://www.FreeBSD.org/handbook/makeworld.html>.
Restart all daemons that use the library, or reboot the system.
VI. Correction details
This issue is corrected by the corresponding Git commit hash or Subversion
revision number in the following stable and release branches:
Branch/path Hash Revision
- -------------------------------------------------------------------------
stable/13/ f9972532343b stable/13-n245792
releng/13.0/ 8acc450613c3 releng/13.0-n244745
stable/12/ r369897
releng/12.2/ r369921
stable/11/ r369896
releng/11.4/ r369919
- -------------------------------------------------------------------------
For FreeBSD 13 and later:
Run the following command to see which files were modified by a
particular commit:
# git show --stat <commit hash>
Or visit the following URL, replacing NNNNNN with the hash:
<URL:https://cgit.freebsd.org/src/commit/?id=NNNNNN>
To determine the commit count in a working tree (for comparison against
nNNNNNN in the table above), run:
# git rev-list --count --first-parent HEAD
For FreeBSD 12 and earlier:
Run the following command to see which files were modified by a particular
revision, replacing NNNNNN with the revision number:
# svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base
Or visit the following URL, replacing NNNNNN with the revision number:
<URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN>
VII. References
The latest revision of this advisory is available at
<URL:https://security.FreeBSD.org/advisories/FreeBSD-EN-21:17.libradius.asc>