CVE-2019-18933
CVE-2019-18933 is a critical-severity vulnerability in Zulip Zulip Server with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- CVSS v2: 7.5
- EPSS exploit prediction: 1% (68th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Zulip Zulip Server
- Published:
- Last modified:
Description
In Zulip Server versions from 1.7.0 to before 2.0.7, a bug in the new user signup process meant that users who registered their account using social authentication (e.g., GitHub or Google SSO) in an organization that also allows password authentication could have their personal API key stolen by an unprivileged attacker, allowing nearly full access to the user's account.
Frequently asked questions
- What is CVE-2019-18933?
- In Zulip Server versions from 1.7.0 to before 2.0.7, a bug in the new user signup process meant that users who registered their account using social authentication (e.g., GitHub or Google SSO) in an organization that also allows password authentication could have their personal API key stolen by an unprivileged attacker, allowing nearly full access to the user's account.
- How severe is CVE-2019-18933?
- CVE-2019-18933 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2019-18933 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-18933?
- CVE-2019-18933 affects Zulip Zulip Server. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2019-18933?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2019-18933 published?
- CVE-2019-18933 was published on 2019-11-21 and last updated on 2026-06-17.
References
- https://blog.zulip.org/2019/11/21/zulip-2-0-7-security-release/
- https://github.com/zulip/zulip/commit/0c2cc41d2e40807baa5ee2c72987ebfb64ea2eb6
Affected products (1)
- cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*
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