CVE-2026-21671

A vulnerability allowing an authenticated user with the Backup Administrator role to perform remote code execution (RCE) in high availability (HA) deployments of Veeam Backup & Replication.

Published: 2026-03-12 Last update: 2026-05-10 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-21671 is rated Moderate Risk (48.7/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.16%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-21671

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-22 0.46% 0.16% -0.30%
2 2026-05-19 0.44% 0.46% +0.02%
3 2026-05-11 — 0.44% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-21671

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.3 6.0 [email protected]

Weakness enumeration for CVE-2026-21671

GitHub Security Advisory for CVE-2026-21671

GHSA-9prx-6fqf-vvjh · Severity: critical — A vulnerability allowing an authenticated user with the Backup Administrator role to perform...

Affected software / configurations for CVE-2026-21671

Vendor Product Version Raw CPE
veeam veeam_backup_\&_replication >= 13.0.0.496, <= 13.0.1.1071 cpe:2.3:a:veeam:veeam_backup_\&_replication:*:*:*:*:*:*:*:*

References for CVE-2026-21671

URL Tags
https://www.veeam.com/kb4831 Vendor Advisory
cvelogic Threat Intelligence