CVE-2026-21666 json
A vulnerability allowing an authenticated domain user to perform remote code execution (RCE) on the Backup Server.
published 7mo ago modified 4mo ago also EUVD-2026-11574
- cvss
- 10.0
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 70%
- public exploits
- 0
- none known
Summary
A vulnerability allowing an authenticated domain user to perform remote code execution (RCE) on the Backup Server.
Patch / fix
- veeam veeam_backup_&_replication 12.3.2.4465
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 7mo ago
Exploit prediction
1.29% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 10.0 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
- Veeam Backup and Replication
Classification
- Weakness
-
- CWE-284 Improper Access Control
References
-
veeam.com
/kb4830
vendor-advisory
Sources
- CVE List CVE-2026-21666
- NVD CVE-2026-21666
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.