CVE-2018-9999
CVE-2018-9999 is a medium-severity vulnerability in Zulip Zulip Server with a CVSS 3.x base score of 5.4. 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 5.4)
- CVSS v2: 3.5
- EPSS exploit prediction: 1% (50th 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 was an XSS issue with user uploads and the (default) LOCAL_UPLOADS_DIR storage backend.
Frequently asked questions
- What is CVE-2018-9999?
- In Zulip Server versions before 1.7.2, there was an XSS issue with user uploads and the (default) LOCAL_UPLOADS_DIR storage backend.
- How severe is CVE-2018-9999?
- CVE-2018-9999 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2018-9999 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2018-9999?
- CVE-2018-9999 affects Zulip Zulip Server. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2018-9999?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2018-9999 published?
- CVE-2018-9999 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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