CVE-2018-20583

Public Exploit

Description

Cross-site scripting (XSS) vulnerability in the PHP League CommonMark library versions 0.15.6 through 0.18.x before 0.18.1 allows remote attackers to insert unsafe URLs into HTML (even if allow_unsafe_links is false) via a newline character (e.g., writing javascript as javascri%0apt).

Category

6.1
CVSS
Severity: Medium
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.33%
Third-Party Advisory thephpleague.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://commonmark.thephpleague.com/changelog/ third party advisory release notes
https://github.com/thephpleague/commonmark/issues/337 third party advisory exploit
https://github.com/thephpleague/commonmark/releases/tag/0.18.1 third party advisory release notes

Frequently Asked Questions

What is the severity of CVE-2018-20583?
CVE-2018-20583 has been scored as a medium severity vulnerability.
How to fix CVE-2018-20583?
To fix CVE-2018-20583, 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-2018-20583 being actively exploited in the wild?
It is possible that CVE-2018-20583 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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