CVE-2019-10905
Parsedown before 1.7.2, when safe mode is used and HTML markup is disabled, might allow attackers to execute arbitrary JavaScript code if a script (already running on the affected page) executes the contents of any element with a specific class.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.47%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Parsedown before 1.7.2, when safe mode is used and HTML markup is disabled, might allow attackers to execute arbitrary JavaScript code if a script (already running on the affected page) executes the contents of any element with a specific class. This occurs because spaces are permitted in code block infostrings, which interferes with the intended behavior of a single class name beginning with the language- substring.
- CVSS 3.0
- 8.1 HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.47% probability · 72th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- parsedown/parsedown
- Source
- cve@mitre.org
References
- https://github.com/erusev/parsedown/issues/699Exploit, Issue Tracking, Third Party Advisory
- https://github.com/erusev/parsedown/releases/tag/1.7.2Release Notes, Third Party Advisory
- https://github.com/erusev/parsedown/issues/699Exploit, Issue Tracking, Third Party Advisory
- https://github.com/erusev/parsedown/releases/tag/1.7.2Release Notes, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.