CVE-2021-26917

Name: CVE-2021-26917
Creator: NVD / NIST
Published: 2021-02-08T23:15:11.973+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.55%

Last modified Jun 17, 2026

CVE-2021-26917 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. PyBitmessage through 0.6.3.2 allows attackers to write screen captures to Potentially Unwanted Directories via a crafted apinotifypath value. NOTE: the discoverer states "security mitigation may not be necessary as there is no evidence yet that these screen intercepts are actually transported away from the local host." NOTE: it is unclear whether there are any common use cases in which apinotifypath is controlled by an attacker. EPSS estimates a 0.55% chance of exploitation in the next 30 days.

Description

PyBitmessage through 0.6.3.2 allows attackers to write screen captures to Potentially Unwanted Directories via a crafted apinotifypath value. NOTE: the discoverer states "security mitigation may not be necessary as there is no evidence yet that these screen intercepts are actually transported away from the local host." NOTE: it is unclear whether there are any common use cases in which apinotifypath is controlled by an attacker

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.55%

41.8th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Bitmessage	Pybitmessage	<= 0.6.3.2

References

https://attack.mitre.org/techniques/T1113/Third Party Advisory
https://github.com/Bitmessage/PyBitmessage/blob/f381721bec31641002e2f240309600c4994855a7/src/api.py#L35-L37Patch, Third Party Advisory
https://github.com/Bitmessage/PyBitmessage/releasesRelease Notes, Third Party Advisory
https://poal.co/s/technology/290479Exploit, Third Party Advisory
https://attack.mitre.org/techniques/T1113/Third Party Advisory
https://github.com/Bitmessage/PyBitmessage/blob/f381721bec31641002e2f240309600c4994855a7/src/api.py#L35-L37Patch, Third Party Advisory
https://github.com/Bitmessage/PyBitmessage/releasesRelease Notes, Third Party Advisory
https://poal.co/s/technology/290479Exploit, Third Party Advisory

Timeline

Published: Feb 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-26917?

How severe is CVE-2021-26917?

CVE-2021-26917 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.55% probability of exploitation in the next 30 days.

How do I fix CVE-2021-26917?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-26917?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST