MarkUs: YAML alias (‘billion laughs’) DoS in config upload
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 4.9epss 0.3%
exploitation probability
0.3%top 79% of all CVEs
observed exploitation
nono source reports it
MarkUs is a web application for the submission and grading of student assignments. Prior to version 2.9.4, MarkUs allows course instructors to upload YAML files to create/update various entities (e.g., assignment settings). These YAML files are parsed with aliases enabled. This issue has been patched in version 2.9.4.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Affected products
MarkUsProject · Markus