CVE-2026-34052

EUVD-2026-18893

03.04.2026, 23:17

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.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	5.9 MEDIUM	NETWORK	HIGH	NONE	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Base Score

CVSS 3.x

EPSS Score

Percentile: 18%

Affected Products (NVD)

Vendor	Product	Version
jupyter	lti_jupyterhub_authenticator	𝑥 < 1.6.3

𝑥

= Vulnerable software versions

Common Weakness Enumeration

CWE-401 - Missing Release of Memory after Effective Lifetime
The software does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

References

https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3

https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj