CVE-2021-26562
Out-of-bounds write vulnerability in synoagentregisterd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to execute arbitrary code via syno_finder_site HTTP header.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.90%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Out-of-bounds write vulnerability in synoagentregisterd in Synology DiskStation Manager (DSM) before 6.2.3-25426-3 allows man-in-the-middle attackers to execute arbitrary code via syno_finder_site HTTP header.
- CVSS 3.1
- 8.1 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.90% probability · 80th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- synology/diskstation manager · synology/vs960hd firmware · synology/skynas firmware · synology/diskstation manager unified controller
- Source
- security@synology.com
EPSS 1.9% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://www.synology.com/security/advisory/Synology_SA_20_26Vendor Advisory
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159Exploit, Third Party Advisory
- https://www.synology.com/security/advisory/Synology_SA_20_26Vendor Advisory
- https://www.talosintelligence.com/vulnerability_reports/TALOS-2020-1159Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.