Incorrect type conversion in isync
Priority LOW 36CWE-704Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-704 and the CVSS impact.
Summary
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.
Why it matters now
EPSS 0.01037 64th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | isync | isync 1.3.6, isync 1.4.2 | — | No fix listed | CNA |
- isync Vendor— Affected isync 1.3.6, isync 1.4.2 Fixed in — No fix listed CNA
CPE configurations NVD · 6
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:isync_project:isync:*:*:*:*:*:*:*:* | before 1.3.6 | Vulnerable | Isync Project |
| cpe:2.3:a:isync_project:isync:1.4.0:*:*:*:*:*:*:* | 1.4.0 | Vulnerable | Isync Project |
| cpe:2.3:a:isync_project:isync:1.4.1:*:*:*:*:*:*:* | 1.4.1 | Vulnerable | Isync Project |
| cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* | 33 | Vulnerable | Fedoraproject |
| cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* | 34 | Vulnerable | Fedoraproject |
| cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Debian |
- cpe:2.3:a:isync_project:isync:*:*:*:*:*:*:*:* Versions before 1.3.6 Vulnerable ·Isync Project
- cpe:2.3:a:isync_project:isync:1.4.0:*:*:*:*:*:*:* Versions 1.4.0 Vulnerable ·Isync Project
- cpe:2.3:a:isync_project:isync:1.4.1:*:*:*:*:*:*:* Versions 1.4.1 Vulnerable ·Isync Project
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject
- cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Debian
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2021-3578
- 2026-10-03 Alias added: GHSA-4r75-vj28-w5c7
References
Patch 3
Advisory 4
Sources
- CVE-2021-3578 · CVE Program
- CVE-2021-3578 · NVD
- FIRST EPSS
- GHSA-4r75-vj28-w5c7 · GitHub Advisory Database · CC BY 4.0
- CVE-2021-3578 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences