Home/CVE/There's a flaw in the zeromq server in versions before 4.3.3 in src/decoder_allocators.hpp. The decoder static allocator
CVE

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

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.

HIGH · CVSS 8.1 EPSS 0.06576
Schedule remediation
  • EPSS percentile: top 9% of all CVEs by exploitation likelihood
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0

Affected Products & Versions

1
zeromq libzmq>= 4.2.0 and < 4.3.3

Scoring & Timeline

8.1
HIGH · CVSS v3.1 · secalert@redhat.com
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD01 Apr 2021 · 02:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Vendor Advisories

1
🔗

References & Sources

2
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.redhat.com/show_bug.cgi?id=1921983Issue TrackingPatchThird Party Advisory
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