CVE-2026-34052 (GCVE-0-2026-34052)

Vulnerability from cvelistv5 – Published: 2026-04-03 22:04 – Updated: 2026-04-06 18:59
VLAI
Title
LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)
Summary
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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-06 18:58 UTC
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8094 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
jupyterhub ltiauthenticator Affected: < 1.6.3
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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