__________________________________________________________________
Squid Proxy Cache Security Update Advisory SQUID-2021:3
__________________________________________________________________
Advisory ID: | SQUID-2021:3
Date: | May 10, 2021
Summary: | Denial of Service issue in Cache Manager
Affected versions: | Squid 1.x -> 3.5.28
| Squid 4.x -> 4.14
| Squid 5.x -> 5.0.4
Fixed in version: | Squid 4.15 and 5.0.5
__________________________________________________________________
<http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-28652>
__________________________________________________________________
Problem Description:
Due to an incorrect parser validation bug Squid is vulnerable to
a Denial of Service attack against the Cache Manager API.
__________________________________________________________________
Severity:
This problem allows a trusted client to trigger memory leaks
which over time lead to a Denial of Service against Squid and
the machine it is operating on.
This attack is limited to clients with Cache Manager API access
privilege.
CVSS Score of 7.8
https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:H/PR:H/UI:N/S:C/C:N/I:N/A:H/E:F/RL:O/RC:C/CR:X/IR:X/AR:H/MAV:N/MAC:H/MPR:H/MUI:N/MS:C/MC:X/MI:X/MA:H&version=3.1
__________________________________________________________________
Updated Packages:
This bug is fixed by Squid versions 4.15 and 5.0.6.
In addition, patches addressing this problem for the stable
releases can be found in our patch archives:
Squid 4:
<http://www.squid-cache.org/Versions/v4/changesets/squid-4-0003e3518dc95e4b5ab46b5140af79b22253048e.patch>
Squid 5:
<http://www.squid-cache.org/Versions/v5/changesets/squid-5-2db70e04723cedd19a90dba8b863ccbc2e708f8e.patch>
If you are using a prepackaged version of Squid then please refer
to the package vendor for availability information on updated
packages.
__________________________________________________________________
Determining if your version is vulnerable:
Squid older than 3.5.28 have not been tested and should be
assumed to be vulnerable.
All Squid-4.x up to and including 4.14 are vulnerable.
All Squid-5.x up to and including 5.0.4 are vulnerable.
__________________________________________________________________
Workaround:
Either,
Disable Cache Manager access entirely if not needed.
Place the following line in squid.conf before lines containing
"allow" :
http_access deny manager
Or,
Harden Cache Manager access privileges.
For example; require authentication or other access controls in
http_access beyond the default IP address restriction.
__________________________________________________________________
Contact details for the Squid project:
For installation / upgrade support on binary packaged versions
of Squid: Your first point of contact should be your binary
package vendor.
If you install and build Squid from the original Squid sources
then the <squid-users@xxxxxxxxxxxxxxxxxxxxx> mailing list is your
primary support point. For subscription details see
<http://www.squid-cache.org/Support/mailing-lists.html>.
For reporting of non-security bugs in the latest STABLE release
the squid bugzilla database should be used
<http://bugs.squid-cache.org/>.
For reporting of security sensitive bugs send an email to the
<squid-bugs@xxxxxxxxxxxxxxxxxxxxx> mailing list. It's a closed
list (though anyone can post) and security related bug reports
are treated in confidence until the impact has been established.
__________________________________________________________________
Credits:
This vulnerability was discovered by Joshua Rogers of Opera
Software.
Fixed by Amos Jeffries of Treehouse Networks Ltd.
__________________________________________________________________
Revision history:
2021-03-03 17:02:25 UTC Initial Report
2021-03-16 01:59:45 UTC Patch Released
2021-03-17 06:19:09 UTC CVE Assignment
__________________________________________________________________
END
_______________________________________________
squid-announce mailing list
squid-announce@xxxxxxxxxxxxxxxxxxxxx
http://lists.squid-cache.org/listinfo/squid-announce
