Vulnerability · Published Feb 16, 2022 · Assigned by redhat

CVE-2021-3578

High 7.8

In plain English

A high-severity security flaw in isync. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.0% (higher than 64% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)7.8High
Exploit odds (30 days)1.0%top 35.9% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.20isync1.4.2-r0ALPINE-CVE-2021-3578
Alpine:v3.21isync1.4.2-r0ALPINE-CVE-2021-3578
Alpine:v3.22isync1.4.2-r0ALPINE-CVE-2021-3578
Alpine:v3.23isync1.4.2-r0ALPINE-CVE-2021-3578
Alpine:v3.24isync1.4.2-r0ALPINE-CVE-2021-3578
Debian:12isync1.3.0-2.2DEBIAN-CVE-2021-3578
Debian:13isync1.3.0-2.2DEBIAN-CVE-2021-3578
Debian:14isync1.3.0-2.2DEBIAN-CVE-2021-3578
Ubuntu:22.04:LTSisyncno fix listedUBUNTU-CVE-2021-3578
Ubuntu:24.04:LTSisyncno fix listedUBUNTU-CVE-2021-3578
Ubuntu:25.10isyncno fix listedUBUNTU-CVE-2021-3578
Ubuntu:26.04:LTSisyncno fix listedUBUNTU-CVE-2021-3578
Ubuntu:26.10isyncno fix listedUBUNTU-CVE-2021-3578

Affected products (as reported)

VendorProductVersions
n/a isync isync 1.3.6, isync 1.4.2

Weakness: CWE-704

References