How severe is CVE-2017-0881?

CVE-2017-0881 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2017-0881 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-0881?

CVE-2017-0881 affects Zulip Zulip Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-0881?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2017-0881 published?

CVE-2017-0881 was published on 2017-03-28 and last updated on 2026-06-17.

CVE-2017-0881

CVE-2017-0881 is a medium-severity vulnerability in Zulip Zulip Server with a CVSS 3.x base score of 4.3. 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-863.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Zulip Zulip Server
Published: 2017-03-28
Last modified: 2026-06-17

Description

An error in the implementation of an autosubscribe feature in the check_stream_exists route of the Zulip group chat application server before 1.4.3 allowed an authenticated user to subscribe to a private stream that should have required an invitation from an existing member to join. The issue affects all previously released versions of the Zulip server.

Frequently asked questions

What is CVE-2017-0881?: An error in the implementation of an autosubscribe feature in the check_stream_exists route of the Zulip group chat application server before 1.4.3 allowed an authenticated user to subscribe to a private stream that should have required an invitation from an existing member to join. The issue affects all previously released versions of the Zulip server.
How severe is CVE-2017-0881?: CVE-2017-0881 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2017-0881 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-0881?: CVE-2017-0881 affects Zulip Zulip Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-0881?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2017-0881 published?: CVE-2017-0881 was published on 2017-03-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:zulip:zulip_server:*:*:*:*:*:*:*:*

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