CVE-2021-33026

Description

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. NOTE: a third party indicates that exploitation is extremely unlikely unless the machine is already compromised; in other cases, the attacker would be unable to write their payload to the cache and generate the required collision

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 20.37% Top 5%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-33026?
CVE-2021-33026 has been scored as a critical severity vulnerability.
How to fix CVE-2021-33026?
To fix CVE-2021-33026, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-33026 being actively exploited in the wild?
It is possible that CVE-2021-33026 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~20% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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