CVE-2021-20235
8.1CVSSHIGH
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.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
and 3 more affected products View all →
Attack Graph
Products CVE Techniques Tactics
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Exploitability
Official Patch Available
MITRE ATT&CK
2 techniques Initial Access
Privilege Escalation
References
https://bugzilla.redhat.com/show_bug.cgi?id=1921983
bugzilla.redhat.com
https://github.com/zeromq/libzmq/security/advisories/GHSA-fc3w-qxf5-7hp6
github.com
https://nvd.nist.gov/vuln/detail/CVE-2021-20235
nvd.nist.gov
and 10 more references View all →
Timeline
Published
Apr 1, 2021
Last Updated
Nov 21, 2024
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