CVE-2026-34052

low-risk
Published 2026-04-03

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.

Do I need to act?

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0.05% chance of exploitation
EPSS score — low exploit probability
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Not on CISA KEV list
No confirmed active exploitation reported to CISA
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Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
5
CVSS 5.9/10 Medium
NETWORK / HIGH complexity

Affected Products (1)

Lti Jupyterhub Authenticator

Affected Vendors

Jupyter

References (2)

Product https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3
Vendor Advisory https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr...
23
/ 100
low-risk
Severity 18/34 · Moderate
Exploitability 0/34 · Minimal
Exposure 5/34 · Minimal