CVE-2025-50864

CVSS 6.5 MediumEPSS 0.0%
  • CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
  • Published: 2025-08-20T15:15:32.990

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.

Related CVE by CWE

No related CWE found.

Top CVE for Vendor

No vendor taxonomy on this entry.

Recently Exploited Similar Vulnerabilities

No recent KEV-listed items for this vendor/product.

How to fix CVE-2025-50864

CVE-2025-50864 is a medium severity vulnerability affecting the affected product.

Description: 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” […]

Exploit Difficulty: MEDIUM
⏱️ Time to exploit: 1-4 hours
🛠️ Required skills: Intermediate security knowledge
💰 Public exploits: May be available

How to Fix:

1 Identify affected systems

- Check if you're running the affected product

2 Immediate actions

- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access

3 Verification

- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)

4 Long-term prevention

- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations

Exploit Difficulty Assessment

MEDIUM
⏱️ Time to Exploit: 1-4 hours
🛠️ Skills Required: Intermediate security knowledge
💰 Public Exploits: May be available

Vulnerability Timeline

Aug 20, 2025
Vulnerability Published

CVE details first published to NVD database

Nov 12, 2025
Imported to Database

Added to this CVE tracking system

Detection Rules & IOCs

No specific detection rules generated for this vulnerability type.

No vendor/product data available.