CVE-2021-3377

Public Exploit

Description

The npm package ansi_up converts ANSI escape codes into HTML. In ansi_up v4, ANSI escape codes can be used to create HTML hyperlinks. Due to insufficient URL sanitization, this feature is affected by a cross-site scripting (XSS) vulnerability. This issue is fixed in v5.0.0.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 30.99% Top 5%
Third-Party Advisory doyensec.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://doyensec.com/resources/Doyensec_Advisory_ansi_up4_XSS.pdf third party advisory exploit
https://github.com/drudru/ansi_up/commit/c8c726ed1db979bae4f257b7fa41775155ba2e27 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-3377?
CVE-2021-3377 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3377?
To fix CVE-2021-3377, 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-2021-3377 being actively exploited in the wild?
It is possible that CVE-2021-3377 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~31% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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