CVE-2021-3420

CRITICAL
9.8
CVSS Score
Published: March 5, 2021 at 07:19 PM UTC
Updated: June 17, 2026 at 04:05 AM UTC
3 products affected across 3 vendorsFedoraNewlibProject Newlib

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Severity
CRITICAL9.8
Exploit prediction
EPSS 2%

Description

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.0.0
Affected range stops below 4.0.0, so it looks safe — our inference, not a vendor statement
v < 4.0.0
Affected range stops below 4.0.0, so it looks safe — our inference, not a vendor statement

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-190

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