CVE-2021-27671

Name: CVE-2021-27671
Creator: NVD / NIST
Published: 2021-02-25T01:15:13.243+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 0.69%

Last modified Jun 17, 2026

CVE-2021-27671 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. An issue was discovered in the comrak crate before 0.9.1 for Rust. XSS can occur because the protection mechanism for data: and javascript: URIs is case-sensitive, allowing (for example) Data: to be used in an attack.. EPSS estimates a 0.69% chance of exploitation in the next 30 days.

Description

An issue was discovered in the comrak crate before 0.9.1 for Rust. XSS can occur because the protection mechanism for data: and javascript: URIs is case-sensitive, allowing (for example) Data: to be used in an attack.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

0.69%

47.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Comrak Project	Comrak	< 0.9.1

References

https://rustsec.org/advisories/RUSTSEC-2021-0026.htmlThird Party Advisory
https://rustsec.org/advisories/RUSTSEC-2021-0026.htmlThird Party Advisory

Timeline

Published: Feb 25, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-27671?

How severe is CVE-2021-27671?

CVE-2021-27671 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 0.69% probability of exploitation in the next 30 days.

How do I fix CVE-2021-27671?

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-2021-27671?

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

Scan your code now

Source: NVD / NIST