CVE-2016-4427
CVE-2016-4427 is a high-severity vulnerability in Zulip with a CVSS 3.x base score of 7.5. 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-284.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- EPSS exploit prediction: 1% (52nd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-284
- Affected product: Zulip
- Published:
- Last modified:
Description
In zulip before 1.3.12, deactivated users could access messages if SSO was enabled.
Frequently asked questions
- What is CVE-2016-4427?
- In zulip before 1.3.12, deactivated users could access messages if SSO was enabled.
- How severe is CVE-2016-4427?
- CVE-2016-4427 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2016-4427 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2016-4427?
- CVE-2016-4427 affects Zulip. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2016-4427?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2016-4427 published?
- CVE-2016-4427 was published on 2022-07-28 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:zulip:zulip:*:*:*:*:*:*:*:*
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