GHSA-656c-6cxf-hvcv

Suggest an improvement
Source
https://github.com/advisories/GHSA-656c-6cxf-hvcv
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/06/GHSA-656c-6cxf-hvcv/GHSA-656c-6cxf-hvcv.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-656c-6cxf-hvcv
Aliases
Published
2021-06-18T18:33:40Z
Modified
2024-02-16T08:16:33.120862Z
Severity
  • CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:H/A:N
Summary
Deserialization of Untrusted Data in Flask-Caching
Details

Flask-Cache adds easy cache support to Flask. The Flask-Caching extension through 1.10.1 for Flask relies on Pickle for serialization, which may lead to remote code execution or local privilege escalation. If an attacker gains access to cache storage (e.g., filesystem, Memcached, Redis, etc.), they can construct a crafted payload, poison the cache, and execute Python code.

However, this is not a high-severity issue, as for an attack like this to work, an attacker must:

  1. Be able to write arbitrary values to the cache
  2. Be able to generate a cache key that will collide with a value being read by the application
  3. Cause the application to read a maliciously-injected value

Any situation where all 3 of those is true is a situation where the application has larger problems; for example, if someone's able to inject malicious cached rendered pages into a Flask app's cache, then they can make the website say literally anything they want, regardless of whether it involves the execution of remote code. Basically, the Pickle vulnerability follows from a website already being extremely vulnerable (due to conditions 1 and 2 being met).

References

Affected packages

PyPI / flask-caching

Package

Name
flask-caching
Purl
pkg:pypi/flask-caching

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0The exact introduced commit is unknown
Last affected
1.10.1

Affected versions

1.*

1.0.0
1.0.1
1.1.0
1.1.1
1.2.0
1.3.0
1.3.1
1.3.2
1.3.3
1.4.0
1.5.0
1.6.0
1.7.0
1.7.1
1.7.2
1.8.0
1.9.0
1.10.0
1.10.1