CVE-2026-33527
Parse Server: Session update endpoint allows overwriting server-generated session fields
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.3
Parse Server: Session update endpoint allows overwriting server-generated session fields
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.
- Record
CVE-2026-33527- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-14974
5.3
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.
- Record
EUVD-2026-14974- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-jc39-686j-wp6q
5.3
Parse Server's Session Update endpoint allows overwriting server-generated session fields
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
- Record
GHSA-jc39-686j-wp6q- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
NVD
5.3
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.
- Record
CVE-2026-33527- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
5.3
Parse Server: Session update endpoint allows overwriting server-generated session fields
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0-alpha.48, 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. This issue has been patched in versions 8.6.57 and 9.6.0-alpha.48.
- Record
CVE-2026-33527- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVGHSA-jc39-686j-wp6q
5.3
Parse Server's Session Update endpoint allows overwriting server-generated session fields
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
- Record
GHSA-jc39-686j-wp6q- CVSS 4.0
- 5.3 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVBIT-parse-2026-33527 No score
Parse Server: Session update endpoint allows overwriting server-generated session fields
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.57 and 9.6.0, 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. This issue has been patched in versions 8.6.57 and 9.6.0
- Record
BIT-parse-2026-33527- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
parse-servernpm |
9.0.0 up to 9.6.0-alpha.48 | 9.6.0-alpha.48 |
parse-servernpm |
before 8.6.57 | 8.6.57 |
parseBitnami |
before 8.6.57, 9.0.0 up to 9.6.0 | 8.6.579.6.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-33527 is a medium vulnerability (CVSS 5.3) in Parse-community Parse-server, published March 24, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 18th percentile. Fixed in parse-server 9.6.0-alpha.48.
References
github.com/parse-community/parse-server/security/advisories/GHSA-jc39-686j-wp6q
github.com/parse-community/parse-server/pull/10263
github.com/parse-community/parse-server/pull/10264
github.com/parse-community/parse-server/commit/26b628c8fb3cc79ea955374769eebcff6f8a8a73
github.com/parse-community/parse-server/commit/ea68fc0b22a6056c9675149469ff57817f7cf984
nvd.nist.gov/vuln/detail/CVE-2026-33527
github.com/advisories/GHSA-jc39-686j-wp6q
github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33527.json
github.com/parse-community/parse-server