CVE-2019-6250
CVE-2019-6250 is a high-severity vulnerability in Zeromq Libzmq with a CVSS 3.x base score of 8.8. 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-190.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v2: 9.0
- EPSS exploit prediction: 9% (95th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-190
- Affected product: Zeromq Libzmq
- Published:
- Last modified:
Description
A pointer overflow, with code execution, was discovered in ZeroMQ libzmq (aka 0MQ) 4.2.x and 4.3.x before 4.3.1. A v2_decoder.cpp zmq::v2_decoder_t::size_ready integer overflow allows an authenticated attacker to overwrite an arbitrary amount of bytes beyond the bounds of a buffer, which can be leveraged to run arbitrary code on the target system. The memory layout allows the attacker to inject OS commands into a data structure located immediately after the problematic buffer (i.e., it is not necessary to use a typical buffer-overflow exploitation technique that changes the flow of control).
Frequently asked questions
- What is CVE-2019-6250?
- A pointer overflow, with code execution, was discovered in ZeroMQ libzmq (aka 0MQ) 4.2.x and 4.3.x before 4.3.1. A v2_decoder.cpp zmq::v2_decoder_t::size_ready integer overflow allows an authenticated attacker to overwrite an arbitrary amount of bytes beyond the bounds of a buffer, which can be leveraged to run arbitrary code on the target system. The memory layout allows the attacker to inject OS commands into a data structure located immediately after the problematic buffer (i.e., it is not necessary to use a typical buffer-overflow exploitation technique that changes the flow of control).
- How severe is CVE-2019-6250?
- CVE-2019-6250 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2019-6250 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-6250?
- CVE-2019-6250 primarily affects Zeromq Libzmq. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-6250?
- 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-2019-6250 published?
- CVE-2019-6250 was published on 2019-01-13 and last updated on 2026-06-17.
References
- https://github.com/zeromq/libzmq/issues/3351
- https://github.com/zeromq/libzmq/releases/tag/v4.3.1
- https://security.gentoo.org/glsa/201903-22
- https://www.debian.org/security/2019/dsa-4368
Affected products (2)
- cpe:2.3:a:zeromq:libzmq:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
More vulnerabilities in Zeromq Libzmq
- CVE-2020-36400 — Critical (CVSS 9.8): ZeroMQ libzmq 4.3.3 has a heap-based buffer overflow in zmq::tcp_read, a different vulnerability than CVE-2021-20235.
- CVE-2019-13132 — Critical (CVSS 9.8): In ZeroMQ libzmq before 4.0.9, 4.1.x before 4.1.7, and 4.2.x before 4.3.2, a remote, unauthenticated client connecting…
- CVE-2021-20235 — High (CVSS 8.1): There's a flaw in the zeromq server in versions before 4.3.3 in src/decoder_allocators.hpp. The decoder static…
- CVE-2021-20237 — High (CVSS 7.5): An uncontrolled resource consumption (memory leak) flaw was found in ZeroMQ's src/xpub.cpp in versions before 4.3.3.…
- CVE-2020-15166 — High (CVSS 7.5): In ZeroMQ before version 4.3.3, there is a denial-of-service vulnerability. Users with TCP transport public endpoints,…
- CVE-2021-20234 — Medium (CVSS 6.5): An uncontrolled resource consumption (memory leak) flaw was found in the ZeroMQ client in versions before 4.3.3 in…
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- CVE-2015-5097 — Critical (CVSS 10.0): Integer overflow in Adobe Reader and Acrobat 10.x before 10.1.15 and 11.x before 11.0.12, Acrobat and Acrobat Reader DC…
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