CVE-2026-40942 DSF: Inverted Time Comparison in OIDC JWKS and Token Cache
Inverted time comparisons in OIDC caches cause excessive network requests and use of expired tokens, leading to potential denial of service and authentication bypass.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-40942?
CVE-2026-40942 is a medium-severity vulnerability in datasharingframework dsf, published on 21 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Data Sharing Framework (DSF) implements a distributed process engine based on the BPMN 2.0 and FHIR R4 standards. Prior to 2.1.0, The OIDC JWKS and Metadata Document caches used an inverted time comparison (isBefore instead of isAfter), causing the cache to never return cached values. Every incoming request triggered a fresh HTTP fetch of the OIDC Metadata Document and JWKS keys from the OIDC provider. The OIDC token cache for the FHIR client connections used an inverted time comparison (isBefore instead of isAfter), causing the cache to never invalidate. Every incoming request returned the same OIDC token even if expired. This vulnerability is fixed in 2.1.0.
Weakness: CWE-670
Which versions are affected by CVE-2026-40942?
4 open source packages ship an affected version, including dev.dsf:dsf-bpe-process-api-v2 and dev.dsf:dsf-bpe-server.
| Package | Affected | Fixed in |
|---|---|---|
dev.dsf:dsf-bpe-process-api-v2 Maven | All versions | None |
dev.dsf:dsf-bpe-process-api-v2 Maven | All versions | None |
dev.dsf:dsf-bpe-server Maven | All versions | None |
dev.dsf:dsf-bpe-server Maven | All versions | None |
How do I fix CVE-2026-40942?
No fix has been published for CVE-2026-40942 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-40942 being exploited?
There is no known exploitation of CVE-2026-40942 in the wild and no public exploit code.
Sources
Also known as GHSA-xmj9-7625-f634.