CVEvulnerability

CVE-2021-20235

8.1 HIGH Published 2021-04-01 Modified 2026-06-17 Official page ↗
Status
Modified
Published
2021-04-01
Last modified
2026-06-17
Assigner
[email protected]
CVSS 3.1 ([email protected])
8.1 HIGH — CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0 ([email protected])
6.8 MEDIUM — AV:N/AC:M/Au:N/C:P/I:P/A:P
Weaknesses
CWE-120, CWE-787

Description

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.

Affected configurations

• zeromq libzmq (>= 4.2.0 < 4.3.3)

Related

Weakness · CWE (2)

  • CWE-120 Buffer Copy without Checking Size of Input weakness
  • CWE-787 Out-of-bounds Write weakness

References