CVE-2021-20235

There's a flaw in the zeromq server in versions before 4.3.3 in src/decoder_allocators.hpp. The decoder static allocator could have its sized changed, but the buffer would remain the same as it is a static buffer. A remote, unauthenticated attacker who sends a crafted request to the zeromq server could trigger a buffer overflow WRITE of arbitrary data if CURVE/ZAP authentication is not enabled. The greatest impact of this flaw is to application availability, data integrity, and confidentiality.

CVSS v3.0 8.1 HIGH
CVSS v2.0 6.8 MEDIUM

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CVSS v3.0 : HIGH

V3 Legend

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

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CVSS v2.0 : MEDIUM

V2 Legend

Vector : AV:N/AC:M/Au:N/C:P/I:P/A:P

Exploitability : 8.6 / Impact : 6.4

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://bugzilla.redhat.com/show_bug.cgi?id=1921983	Issue Tracking Patch Third Party Advisory
https://github.com/zeromq/libzmq/security/advisories/GHSA-fc3w-qxf5-7hp6	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:zeromq:libzmq:*:*:*:*:*:*:*:*

Information

Published : 2021-04-01 07:15

Updated : 2022-08-05 10:41

NVD link : CVE-2021-20235

Mitre link : CVE-2021-20235

JSON object : View

CWE

CWE-787

Out-of-bounds Write

Products Affected

zeromq

libzmq

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