CVE-2018-19787

Ubuntu Security Notice USN-3841-1

Severity Score

6.1

*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

An issue was discovered in lxml before 4.2.5. lxml/html/clean.py in the lxml.html.clean module does not remove javascript: URLs that use escaping, allowing a remote attacker to conduct XSS attacks, as demonstrated by "j a v a s c r i p t:" in Internet Explorer. This is a similar issue to CVE-2014-3146.

Se ha descubierto un problema en lxml en versiones anteriores a la 4.2.5. lxml/html/clean.py en el módulo lxml.html.clean no elimina las URL javascript: que utilizan escapado, permitiendo que un atacante remoto realice ataques Cross-Site Scripting (XSS), tal y como queda demostrado con "j a v a s c r i p t:" en Internet Explorer. Este es un problema aparte, pero similar a CVE-2014-3146.

USN-3841-1 fixed a vulnerability in lxml. This update provides the corresponding update for Ubuntu 12.04 ESM. It was discovered that lxml incorrectly handled certain HTML files. An attacker could possibly use this issue to conduct cross-site scripting attacks. Various other issues were also addressed.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2018-12-02 CVE Reserved
2018-12-02 CVE Published
2024-08-05 CVE Updated
2025-04-02 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CAPEC

References (5)

URL	Tag	Source
https://lists.debian.org/debian-lts-announce/2018/12/msg00001.html	Mailing List
https://lists.debian.org/debian-lts-announce/2020/11/msg00044.html	Mailing List

URL	Date	SRC

URL	Date	SRC
https://github.com/lxml/lxml/commit/6be1d081b49c97cfd7b3fbd934a193b668629109	2020-11-26

URL	Date	SRC
https://usn.ubuntu.com/3841-1	2020-11-26
https://usn.ubuntu.com/3841-2	2020-11-26

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Lxml Search vendor "Lxml"		Lxml Search vendor "Lxml" for product "Lxml"				< 4.2.5 Search vendor "Lxml" for product "Lxml" and version " < 4.2.5"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				8.0 Search vendor "Debian" for product "Debian Linux" and version "8.0"		-		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				12.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "12.04"		esm		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				14.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "14.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				16.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "16.04"		lts		Affected
Canonical Search vendor "Canonical"		Ubuntu Linux Search vendor "Canonical" for product "Ubuntu Linux"				18.04 Search vendor "Canonical" for product "Ubuntu Linux" and version "18.04"		lts		Affected