CVE-2021-3578

HIGH
7.8
CVSS Score
Published: February 16, 2022 at 06:35 PM UTC
Updated: June 17, 2026 at 04:05 AM UTC
3 products affected across 3 vendorsDebian LinuxFedoraIsync

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Severity
HIGH7.8
Exploit prediction
EPSS 1%

Description

A flaw was found in mbsync before v1.3.6 and v1.4.2, where an unchecked pointer cast allows a malicious or compromised server to write an arbitrary integer value past the end of a heap-allocated structure by issuing an unexpected APPENDUID response. This could be plausibly exploited for remote code execution on the client.

Affected

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

Affected range stops below 1.3.6, so it looks safe — our inference, not a vendor statement

CVSS

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

Quick Info

StatusMODIFIED
CWE
CWE-704

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