Medium 5.9Published Apr 3, 2026

CVE-2026-34052LTI JupyterHub Authenticator: Unbounded Memory Growth via Nonce Storage (Denial of Service)

Updated under an hour ago (Oct 26, 2026, 3:50 PM ET)

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It affects jupyterhub ltiauthenticator and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for jupyterhub ltiauthenticator

Exploited in the last 30 days

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.

CVSS: 5.9 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-401, CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 6, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

jupyterhub ltiauthenticator jupyterhub:ltiauthenticator (from the name)	before 1.6.3	CNA record
jupyter lti_jupyterhub_authenticator jupyter:lti_jupyterhub_authenticator	before 1.6.3	NVD

References

References

https://github.com/jupyterhub/ltiauthenticator/security/advisories/GHSA-8mxq-7xr7-2fxj	x-refsource-confirm, vendor-advisory
https://github.com/jupyterhub/ltiauthenticator/releases/tag/1.6.3	x-refsource-misc, product

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.