CVE-2026-34052
MediumCVSS 5.9Exploitation Probability (EPSS)
Low risk25th percentile - higher than 25% of all known CVEs
Summary
In LTI JupyterHub Authenticator prior to version 1.6.3, the LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service.
Risk Assessment
This vulnerability enables a DoS attack that can crash the JupyterHub server, disrupting user work.
Recommendation
Update LTI JupyterHub Authenticator to version 1.6.3 or later.
Original NVD description (English source)
LTI JupyterHub Authenticator is a JupyterHub authenticator for LTI. Prior to version 1.6.3, the LTI 1.1 validator stores OAuth nonces in a class-level dictionary that grows without bounds. Nonces are added before signature validation, so an attacker with knowledge of a valid consumer key can send repeated requests with unique nonces to gradually exhaust server memory, causing a denial of service. This issue has been patched in version 1.6.3.