Parse Server's Session Update endpoint allows overwriting server-generated session fieldsGHSA-jc39-686j-wp6q
MEDIUMFix: parse-community/parse-server#10263GHSA-jc39-686j-wp6q is a medium-severity (CVSS 4.3) CWE-863 vulnerability in parse-server. A fix is available for parse-server — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-jc39-686j-wp6q.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
parse-servernpmDescription
Impact
An authenticated user can overwrite server-generated session fields such as expiresAt and createdWith when updating their own session via the REST API. This allows bypassing the server's configured session lifetime policy, making a session effectively permanent.
Patches
The fix blocks authenticated users from setting expiresAt and createdWith fields when updating a session. Master key and maintenance key operations are not affected.
Workarounds
There is no known workaround other than upgrading.
Resources
- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-jc39-686j-wp6q
- Fix Parse Server 9: https://github.com/parse-community/parse-server/pull/10263
- Fix Parse Server 8: https://github.com/parse-community/parse-server/pull/10264
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | parse-server | ≥ 9.0.0&&< 9.6.0-alpha.48 | 9.6.0-alpha.48npm install parse-server@9.6.0-alpha.48 |
| 📦npm | parse-server | all versions | 8.6.57npm install parse-server@8.6.57 |
Affected Products
parse-serverparseplatformDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update parse-server to 9.6.0-alpha.48 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jc39-686j-wp6q is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-jc39-686j-wp6q in your dependencies?
Find it across npm, including transitive dependencies.