CVE-2018-21259
MEDIUMCVSS 5.3/10EPSS 1.10%
Last modified
CVE-2018-21259 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.. EPSS estimates a 1.10% chance of exploitation in the next 30 days.
Description
An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost Server | < 4.8.2 |
| Mattermost | Mattermost Server | >= 4.9.0, < 4.9.4 |
| Mattermost | Mattermost Server | >= 4.10.0, < 4.10.1 |
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-2018-21259?
An issue was discovered in Mattermost Server before 4.10.1, 4.9.4, and 4.8.2. It allows attackers to cause a denial of service (application hang) via a malformed link in a channel.
How severe is CVE-2018-21259?
CVE-2018-21259 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 1.10% probability of exploitation in the next 30 days.
How do I fix CVE-2018-21259?
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 2018
- CVE-2018-21253An issue was discovered in Mattermost Server before 5.1, 5.0…4.3
- CVE-2018-21254An issue was discovered in Mattermost Server before 5.1. An …4.3
- CVE-2018-21255An issue was discovered in Mattermost Server before 5.1. Non…4.3
- CVE-2018-21256An issue was discovered in Mattermost Server before 5.1. It …4.3
- CVE-2018-21257An issue was discovered in Mattermost Server before 5.1. It …5.3
- CVE-2018-21258An issue was discovered in Mattermost Server before 5.1. It …7.5
- CVE-2018-2126Rejected reason: DO NOT USE THIS CANDIDATE NUMBER. ConsultI…
- CVE-2018-21260An issue was discovered in Mattermost Server before 4.8.1, 4…2.7
- CVE-2018-21261An issue was discovered in Mattermost Server before 4.8.1, 4…4.3
- CVE-2018-21262An issue was discovered in Mattermost Server before 4.7.3. I…7.5
- CVE-2018-21263An issue was discovered in Mattermost Server before 4.7.0, 4…8.8
- CVE-2018-21264An issue was discovered in Mattermost Server before 4.7.0, 4…8.8
Are you affected by CVE-2018-21259?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST