CVE-2018-9986
CVE-2018-9986 is a medium-severity vulnerability in Zulip Zulip Server with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Medium (CVSS 3.x base score 6.1)
- CVSS v2: 4.3
- EPSS exploit prediction: 1% (53rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Zulip Zulip Server
- Published:
- Last modified:
Description
In Zulip Server versions before 1.7.2, there were XSS issues with the frontend markdown processor.
Frequently asked questions
- What is CVE-2018-9986?
- In Zulip Server versions before 1.7.2, there were XSS issues with the frontend markdown processor.
- How severe is CVE-2018-9986?
- CVE-2018-9986 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2018-9986 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2018-9986?
- CVE-2018-9986 affects Zulip Zulip Server. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2018-9986?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2018-9986 published?
- CVE-2018-9986 was published on 2018-04-18 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*
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