Medium severity · published Dec 30, 2018
CVE-2018-20583
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…
6.1
CVSS
1.9%
EPSS
No
On KEV
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).
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.9% · higher than 79% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CO
Commonmark · Thephpleague
0.15.6 through 0.18.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-20583
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-20583
Release Notes
https://commonmark.thephpleague.com/changelog/
Exploit
https://github.com/thephpleague/commonmark/issues/337
Release Notes
https://github.com/thephpleague/commonmark/releases/tag/0.18.1
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