CVE-2014-9721
CVE-2014-9721 is a medium-severity vulnerability in Zeromq with a CVSS 2.0 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-20.
Key facts
- Severity: Medium (CVSS 2.0 base score 4.3)
- EPSS exploit prediction: 3% (83rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Zeromq
- Published:
- Last modified:
Description
libzmq before 4.0.6 and 4.1.x before 4.1.1 allows remote attackers to conduct downgrade attacks and bypass ZMTP v3 protocol security mechanisms via a ZMTP v2 or earlier header.
Frequently asked questions
- What is CVE-2014-9721?
- libzmq before 4.0.6 and 4.1.x before 4.1.1 allows remote attackers to conduct downgrade attacks and bypass ZMTP v3 protocol security mechanisms via a ZMTP v2 or earlier header.
- How severe is CVE-2014-9721?
- CVE-2014-9721 has a CVSS 2.0 base score of 4.3, rated medium severity.
- Is CVE-2014-9721 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2014-9721?
- CVE-2014-9721 primarily affects Zeromq. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2014-9721?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2014-9721 published?
- CVE-2014-9721 was published on 2015-06-03 and last updated on 2026-06-17.
References
- http://lists.fedoraproject.org/pipermail/package-announce/2015-May/159176.html
- http://lists.opensuse.org/opensuse-updates/2015-06/msg00018.html
- http://www.debian.org/security/2015/dsa-3255
- https://github.com/zeromq/libzmq/issues/1273
- https://github.com/zeromq/zeromq4-x/commit/b6e3e0f601e2c1ec1f3aac880ed6a3fe63043e51
Affected products (2)
- cpe:2.3:a:zeromq:zeromq:*:*:*:*:*:*:*:*
- cpe:2.3:a:zeromq:zeromq:4.1.0:rc1:*:*:*:*:*:*
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