GHSA-m6xf-fq7q-8743

Source

https://github.com/advisories/GHSA-m6xf-fq7q-8743

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2020/03/GHSA-m6xf-fq7q-8743/GHSA-m6xf-fq7q-8743.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-m6xf-fq7q-8743

Aliases

Published

2020-03-24T15:06:32Z

Modified

2024-09-12T20:50:49.651546Z

Severity

6.1 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N CVSS Calculator
5.3 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N CVSS Calculator

Summary

Bleach vulnerable to mutation XSS via whitelisted math or svg and raw tag

Details

Impact

A mutation XSS affects users calling bleach.clean with all of:

the svg or math in the allowed/whitelisted tags
an RCDATA tag (see below) in the allowed/whitelisted tags
the keyword argument strip=False

Patches

Users are encouraged to upgrade to bleach v3.1.2 or greater.

Workarounds

modify bleach.clean calls to use strip=True, or not whitelist math or svg tags and one or more of the following tags:
```
script
noscript
style
noframes
xmp
noembed
iframe
```
A strong Content-Security-Policy without unsafe-inline and unsafe-eval script-srcs) will also help mitigate the risk.

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1621692
https://cure53.de/fp170.pdf
https://nvd.nist.gov/vuln/detail/CVE-2020-6816
https://www.checkmarx.com/blog/vulnerabilities-discovered-in-mozilla-bleach

Credits

Reported by Yaniv Nizry from the CxSCA AppSec group at Checkmarx

For more information

If you have any questions or comments about this advisory:

Open an issue at https://github.com/mozilla/bleach/issues
Email us at security@mozilla.org

Database specific

{
    "nvd_published_at": "2020-03-24T22:15:00Z",
    "cwe_ids": [
        "CWE-79"
    ],
    "severity": "MODERATE",
    "github_reviewed": true,
    "github_reviewed_at": "2020-03-23T22:25:38Z"
}

References

Affected packages

PyPI / bleach

Package

Name: bleach; View open source insights on deps.dev
Purl: pkg:pypi/bleach

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

3.1.2

Affected versions

0.*

0.1

0.1.1

0.1.2

0.2

0.2.1

0.2.2

0.3

0.3.1

0.3.3

0.3.4

0.5.0

0.5.1

1.*

1.0.0

1.0.1

1.0.2

1.0.3

1.0.4

1.1.0

1.1.1

1.1.2

1.1.3

1.1.4

1.1.5

1.2

1.2.1

1.2.2

1.4

1.4.1

1.4.2

1.4.3

1.5.0

2.*

2.0.0

2.1

2.1.1

2.1.2

2.1.3

2.1.4

3.*

3.0.0

3.0.1

3.0.2

3.1.0

3.1.1