Bleach URI Scheme Restriction Bypass · CVE-2018-7753 · GitHub Advisory Database · GitHub

Bleach URI Scheme Restriction Bypass

Critical severity GitHub Reviewed Published Jan 4, 2019 to the GitHub Advisory Database • Updated Sep 5, 2023

Package

bleach (pip)

Affected versions

>= 2.1.0, < 2.1.3

Patched versions

2.1.3

Description

An issue was discovered in Bleach 2.1.x before 2.1.3. Attributes that have URI values weren't properly sanitized if the values contained character entities. Using character entities, it was possible to construct a URI value with a scheme that was not allowed that would slide through unsanitized.

References

Published to the GitHub Advisory Database Jan 4, 2019

Reviewed Jun 16, 2020

Last updated Sep 5, 2023

Severity

Critical

9.8

/ 10

CVSS base metrics

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H