CVE-2021-3311

Public Exploit

Description

An issue was discovered in October through build 471. It reactivates an old session ID (which had been invalid after a logout) once a new login occurs. NOTE: this violates the intended Auth/Manager.php authentication behavior but, admittedly, is only relevant if an old session ID is known to an attacker.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.52% Top 20%
Vendor Advisory octobercms.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://octobercms.com/forum/chan/announcements vendor advisory
https://github.com/octobercms/library/commit/642f597489e6f644d4bd9a0c267e864cabead024 third party advisory patch
https://anisiosantos.me/october-cms-token-reactivation third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-3311?
CVE-2021-3311 has been scored as a critical severity vulnerability.
How to fix CVE-2021-3311?
To fix CVE-2021-3311, 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-2021-3311 being actively exploited in the wild?
It is possible that CVE-2021-3311 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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