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:
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.
References
Acknowledgements
We would like to thank Felix Wilhelm of Google's Project Zero for reporting this vulnerability
For more information
If you have any questions or comments about this advisory:
Impact
CommonMarker uses
cmark-gfmfor rendering Github Flavored Markdown. An integer overflow incmark-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:
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.References
Acknowledgements
We would like to thank Felix Wilhelm of Google's Project Zero for reporting this vulnerability
For more information
If you have any questions or comments about this advisory: