ADVISORIES
GEM
SEVERITY
CVSS v3.x: 8.8 (High)
PATCHED VERSIONS
- >= 0.23.4
DESCRIPTION
Impact
CommonMarker uses cmark-gfm for rendering Github Flavored Markdown.
An integer overflow in cmark-gfm’s table row parsing
may lead to heap memory corruption when parsing tables who’s marker rows contain more than UINT16_MAX
columns. The impact of this heap corruption ranges from Information Leak to Arbitrary Code Execution.
If affected versions of CommonMarker are used for rendering remote user controlled markdown, this vulnerability may lead to Remote Code Execution (RCE).
Patches
This vulnerability has been patched in the following CommonMarker release:
- v0.23.4
Workarounds
The vulnerability exists in the table markdown extensions of cmark-gfm. Disabling any use of the
table extension will prevent this vulnerability from being triggered.