lxml up to 3.2.0 lxml.html.clean clean_html incomplete blacklist

CVSS Meta Temp Score
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CTI Interest Score
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3.9$0-$5k0.00

A vulnerability classified as problematic was found in lxml up to 3.2.0. Affected by this vulnerability is the function clean_html of the file lxml.html.clean. The manipulation with an unknown input leads to a incomplete blacklist vulnerability. The CWE definition for the vulnerability is CWE-184. The product implements a protection mechanism that relies on a list of inputs (or properties of inputs) that are not allowed by policy or otherwise require other action to neutralize before additional processing takes place, but the list is incomplete, leading to resultant weaknesses. As an impact it is known to affect integrity. The summary by CVE is:

Incomplete blacklist vulnerability in the lxml.html.clean module in lxml before 3.3.5 allows remote attackers to conduct cross-site scripting (XSS) attacks via control characters in the link scheme to the clean_html function.

The weakness was disclosed 05/14/2014 (Website). The advisory is shared at mailman-mail5.webfaction.com. This vulnerability is known as CVE-2014-3146 since 05/02/2014. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details and also a public exploit are known. MITRE ATT&CK project uses the attack technique T1562.006 for this issue.

It is possible to download the exploit at securityfocus.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 74136 (Ubuntu 12.04 LTS / 13.10 / 14.04 LTS : lxml vulnerability (USN-2217-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176779 (Debian Security Update for lxml (DLA 1604-1)).

Upgrading to version 3.2.1 eliminates this vulnerability.

The vulnerability is also documented in the databases at X-Force (93080) and Tenable (74136). The entry 127380 is pretty similar.

Productinfo

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Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 3.9

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Incomplete blacklist
CWE: CWE-184 / CWE-183 / CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 74136
Nessus Name: Ubuntu 12.04 LTS / 13.10 / 14.04 LTS : lxml vulnerability (USN-2217-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 702941
OpenVAS Name: Debian Security Advisory DSA 2941-1 (lxml - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: lxml 3.2.1

Timelineinfo

04/15/2014 🔍
04/30/2014 +15 days 🔍
05/02/2014 +2 days 🔍
05/14/2014 +12 days 🔍
05/14/2014 +0 days 🔍
05/20/2014 +6 days 🔍
05/22/2014 +2 days 🔍
03/25/2015 +307 days 🔍
03/21/2022 +2553 days 🔍

Sourcesinfo

Advisory: USN-2217-1
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2014-3146 (🔍)
OVAL: 🔍

X-Force: 93080
Vulnerability Center: 44571 - Lxml <3.3.5 XSS Vulnerability in the Lxml.html.clean Module, Medium
SecurityFocus: 67159
Secunia: 58013 - lxml "clean_html()" HTML Cleaning Bypass Vulnerability, Less Critical

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 03/25/2015 16:45
Updated: 03/21/2022 14:21
Changes: 03/25/2015 16:45 (70), 05/28/2017 03:25 (8), 03/21/2022 14:18 (3), 03/21/2022 14:21 (1)
Complete: 🔍

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