CVE-2019-20866
MEDIUMCVSS 5.3/10EPSS 0.92%
Last modified
CVE-2019-20866 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. An issue was discovered in Mattermost Server before 5.12.0. Use of a Proxy HTTP header, rather than the source address in an IP packet header, for obtaining IP address information was mishandled.. EPSS estimates a 0.92% chance of exploitation in the next 30 days.
Description
An issue was discovered in Mattermost Server before 5.12.0. Use of a Proxy HTTP header, rather than the source address in an IP packet header, for obtaining IP address information was mishandled.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | < 5.12.0 |
References
- https://mattermost.com/security-updates/Vendor Advisory
- https://mattermost.com/security-updates/Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2019-20866?
An issue was discovered in Mattermost Server before 5.12.0. Use of a Proxy HTTP header, rather than the source address in an IP packet header, for obtaining IP address information was mishandled.
How severe is CVE-2019-20866?
CVE-2019-20866 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.92% probability of exploitation in the next 30 days.
How do I fix CVE-2019-20866?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2019
- CVE-2019-20860An issue was discovered in Mattermost Server before 5.14.0, …5.5
- CVE-2019-20861An issue was discovered in Mattermost Desktop App before 4.2…8.8
- CVE-2019-20862An issue was discovered in Mattermost Server before 5.13.0. …7.5
- CVE-2019-20863An issue was discovered in Mattermost Server before 5.13.0. …7.5
- CVE-2019-20864An issue was discovered in Mattermost Plugins before 5.13.0.…7.5
- CVE-2019-20865An issue was discovered in Mattermost Server before 5.12.0, …8.8
- CVE-2019-20867An issue was discovered in Mattermost Server before 5.11.0. …5.3
- CVE-2019-20868An issue was discovered in Mattermost Server before 5.11.0. …7.5
- CVE-2019-20869An issue was discovered in Mattermost Server before 5.10.0, …5.3
- CVE-2019-2087In libxaac, there is a possible out of bounds write due to a…8.8
- CVE-2019-20870An issue was discovered in Mattermost Server before 5.10.0. …4.3
- CVE-2019-20871An issue was discovered in Mattermost Server before 5.9.0, 5…7.5
Are you affected by CVE-2019-20866?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST