FreeBSD Security Advisory FreeBSD-SA-20:01.libfetch
28 January, 2020 by security-advisories@freebsd.org | freebsd
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512
=============================================================================
FreeBSD-SA-20:01.libfetch Security Advisory
The FreeBSD Project
Topic: libfetch buffer overflow
Category: core
Module: libfetch
Announced: 2020-01-28
Credits: Duncan Overbruck
Affects: All supported versions of FreeBSD.
Corrected: 2020-01-28 18:40:55 UTC (stable/12, 12.1-STABLE)
2020-01-28 18:55:25 UTC (releng/12.1, 12.1-RELEASE-p2)
2020-01-28 18:55:25 UTC (releng/12.0, 12.0-RELEASE-p13)
2020-01-28 18:42:06 UTC (stable/11, 11.3-STABLE)
2020-01-28 18:55:25 UTC (releng/11.3, 11.3-RELEASE-p6)
CVE Name: CVE-2020-7450
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit <URL:https://security.FreeBSD.org/>.
I. Background
libfetch(3) is a multi-protocol file transfer library included with FreeBSD
and used by the fetch(1) command-line tool, pkg(8) package manager, and
others.
II. Problem Description
A programming error allows an attacker who can specify a URL with a username
and/or password components to overflow libfetch(3) buffers.
III. Impact
An attacker in control of the URL to be fetched (possibly via HTTP redirect)
may cause a heap buffer overflow, resulting in program misbehavior or
malicious code execution.
IV. Workaround
No workaround is available.
V. Solution
Upgrade your vulnerable 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 vulnerable system via a binary patch:
Systems running a RELEASE version of FreeBSD on the i386 or amd64
platforms can be updated via the freebsd-update(8) utility:
# freebsd-update fetch
# freebsd-update install
2) To update your vulnerable 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/SA-20:01/libfetch.patch
# fetch https://security.FreeBSD.org/patches/SA-20:01/libfetch.patch.asc
# gpg --verify libfetch.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
The following list contains the correction revision numbers for each
affected branch.
Branch/path Revision
- -------------------------------------------------------------------------
stable/12/ r357213
releng/12.1/ r357217
releng/12.0/ r357217
stable/11/ r357214
releng/11.3/ r357217
- -------------------------------------------------------------------------
To see which files were modified by a particular revision, run the
following command, replacing NNNNNN with the revision number, on a
machine with Subversion installed:
# 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
<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-7450>
The latest revision of this advisory is available at
<URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-20:01.libfetch.asc>
-----BEGIN PGP SIGNATURE-----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chN4
-----END PGP SIGNATURE-----
_______________________________________________
freebsd-announce@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-announce
To unsubscribe, send any mail to "freebsd-announce-unsubscribe@freebsd.org"