CVE-2021-26567
Synology
- Published
- 26 February 2021
- Last modified
- 17 June 2026
- CVSS
- 7.8 v3.1
- Severity
- high
- EPSS
- 1.1% (64th pct)
- CISA KEV
- Not listed
- NVD status
- Modified
- Weaknesses
- CWE-121, CWE-787
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
Stack-based buffer overflow vulnerability in frontend/main.c in faad2 before 2.2.7.1 allow local attackers to execute arbitrary code via filename and pathname options.
Exploitation
Not listed in the CISA Known Exploited Vulnerabilities catalogue as of 2026.09.04. That is an absence of confirmed public exploitation, not evidence that exploitation has not occurred. EPSS models a 1.1% probability of exploitation activity in the next 30 days.
Affected products
| Product | Vendor | Type | Versions named |
|---|---|---|---|
| VS960HD | Synology | unknown | < 2.2.3-1505, < 2.3.6-1720 |
References
Vendor advisory and patch
- https://www.synology.com/security/advisory/Synology_SA_20_26
- https://www.synology.com/security/advisory/Synology_SA_20_26
- https://github.com/knik0/faad2/commit/720f7004d6c4aabee19aad16e7c456ed76a3ebfa
- https://github.com/knik0/faad2/commit/720f7004d6c4aabee19aad16e7c456ed76a3ebfa
Record assembled from NVD, CISA KEV 2026.09.04 and FIRST EPSS 2026-09-04. Affected products are those NVD's CPE configuration names that fall inside this site's scope; a CVE may affect products outside it.