CVE-2020-15049: XSS

Published Jun 30, 2020
·
Updated

An issue was discovered in http/ContentLengthInterpreter.cc in Squid before 4.12 and 5.x before 5.0.3. A Request Smuggling and Poisoning attack can succeed against the HTTP cache. The client sends an HTTP request with a Content-Length header containing "+\ "-" or an uncommon shell whitespace character prefix to the length field-value.

Other sources

Squid-Cache Squid is vulnerable to HTTP request smuggling, caused by improper input validation. By sending specially crafted HTTP(S) request messages, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.

IBM

Affected Software

21 affected componentsFixes available
IBM Security Guardium<=10.5
IBM Security Guardium<=10.6
IBM Security Guardium<=11.0
IBM Security Guardium<=11.1
IBM Security Guardium<=11.2
IBM Security Guardium<=11.3
Squid-Cache Squid>=2.0<=2.6
Squid-Cache Squid>=3.1<=3.5.28
Squid-Cache Squid>=4.0<4.12
Squid-Cache Squid>=5.0<5.0.3
Squid-Cache Squid=2.7
Squid-Cache Squid=2.7-stable2
Squid-Cache Squid=2.7-stable3
Squid-Cache Squid=2.7-stable4
Squid-Cache Squid=2.7-stable5
Squid-Cache Squid=2.7-stable6
Squid-Cache Squid=2.7-stable7
Squid-Cache Squid=2.7-stable8
Squid-Cache Squid=2.7-stable9
Fedoraproject Fedora=31
debian/squid
4.13-10+deb11u34.13-10+deb11u65.7-2+deb12u55.7-2+deb12u46.13-2+deb13u17.5-1

Event History

Jun 30, 2020
CVE Published
via MITRE·05:55 PM
Data Sourced
via MITRE·05:55 PM
DescriptionSeverity
Data Sourced
via NVD·06:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Feb 23, 2026
Data Sourced
via Ubuntu·07:43 PM
RemedyDescriptionSeverityAffected Software
Data Sourced
via Launchpad·07:44 PM
Description
Apr 1, 2026
Data Sourced
via Debian·08:07 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2020-15049?

CVE-2020-15049 is a vulnerability in Squid-Cache Squid that allows for HTTP request smuggling due to improper input validation.

2

What is the severity of CVE-2020-15049?

CVE-2020-15049 has a severity rating of critical, with a CVSS score of 9.9.

3

How does CVE-2020-15049 affect Squid?

CVE-2020-15049 affects Squid versions before 4.12 and 5.x before 5.0.3.

4

How can I fix CVE-2020-15049 in Squid?

To fix CVE-2020-15049 in Squid, update to version 4.12 or 5.0.3 or later.

5

Where can I find more information about CVE-2020-15049?

More information about CVE-2020-15049 can be found at the following references: - [http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html](http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00012.html) - [http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html](http://lists.opensuse.org/opensuse-security-announce/2020-09/msg00017.html) - [http://www.squid-cache.org/Versions/v4/changesets/squid-4-ea12a34d338b962707d5078d6d1fc7c6eb119a22.patch](http://www.squid-cache.org/Versions/v4/changesets/squid-4-ea12a34d338b962707d5078d6d1fc7c6eb119a22.patch)

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