CVE-2025-50864 json
elysia-cors Origin Validation Error
published 2025-08-20 14 mo ago modified 2026-07-05 4 mo ago also GHSA-f9qj-4c5x-cpcw , EUVD-2025-25313
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
An Origin Validation Error in the elysia-cors library thru 1.3.0 allows attackers to bypass Cross-Origin Resource Sharing (CORS) restrictions. The library incorrectly validates the supplied origin by checking if it is a substring of any domain in the site's CORS policy, rather than performing an exact match. For example, a malicious origin like "notexample.com", "example.common.net" is whitelisted when the site's CORS policy specifies "example.com." This vulnerability enables unauthorized access to user data on sites using the elysia-cors library for CORS validation.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 14 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
| GitHub | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @elysiajs/cors | <1.3.1 |
1.3.1 |
Classification
References
-
github.com
/elysiajs/elysia-cors/commit/9b9eb92e32a7a4b43b6d5108668941701c33e221
web
-
github.com
/elysiajs/elysia-cors/blob/main/src/index.ts
web
-
github.com
/elysiajs/elysia-cors/tree/main
web
-
medium.com
/@raghavagrawal_23036/cors-bypass-in-popular-opensource-library-ad27fb41e16a
web
-
nvd.nist.gov
/vuln/detail/CVE-2025-50864
advisory
-
github.com
/elysiajs/elysia-cors
package
-
elysiajs.com
web
Sources
- CVE List CVE-2025-50864
- GitHub Advisory GHSA-f9qj-4c5x-cpcw
- NVD CVE-2025-50864
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.