CVE-2021-33500

Public Exploit

Description

PuTTY before 0.75 on Windows allows remote servers to cause a denial of service (Windows GUI hang) by telling the PuTTY window to change its title repeatedly at high speed, which results in many SetWindowTextA or SetWindowTextW calls. NOTE: the same attack methodology may affect some OS-level GUIs on Linux or other platforms for similar reasons.

7.5

CVSS

Severity: High

CVSS 3.1 •

CVSS 2.0 •

EPSS 0.40%

Third-Party Advisory ssh-mitm.at Third-Party Advisory github.com Third-Party Advisory org.uk

Affected: n/a n/a

References

Link	Tags
https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html	third party advisory release notes
https://docs.ssh-mitm.at/puttydos.html	third party advisory exploit
https://github.com/ssh-mitm/ssh-mitm-plugins/blob/main/ssh_mitm_plugins/ssh/putty_dos.py	third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-33500?: CVE-2021-33500 has been scored as a high severity vulnerability.
How to fix CVE-2021-33500?: To fix CVE-2021-33500, 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-2021-33500 being actively exploited in the wild?: It is possible that CVE-2021-33500 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.

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