CVE-2023-2868: Barracuda Networks ESG Appliance Improper Input Validation Vulnerability
Affects Barracuda Networks Email Security Gateway (ESG) ApplianceSource CISA KEV
Exploited in the wild · KEV due 16 Jun 2023 · public exploit available (Metasploit) · 86% EPSS : apply the vendor's fix or mitigations to Barracuda Networks Email Security Gateway (ESG) Appliance now.
Data as of 10/24/2026, 22:15:59 UTC
- Exploitation
Actively exploited – in CISA KEV since 05/26/2023
- KEV deadline
- 06/16/2023 US federal agencies must patch by this date; a sensible deadline for everyone else.
- EPSS
- 86.8% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Public exploits
- 1 Metasploit modulePublic attack or detection tooling exists; see Public exploits below.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:LWhat to do
CISA required action
Apply updates per vendor instructions.
Check the firmware or software version for Barracuda Networks Email Security Gateway (ESG) Appliance in the device's admin interface against the vendor advisory.
Public exploits and detection
Metasploit modules
Public tooling indexed from Metasploit Framework, Exploit-DB and ProjectDiscovery nuclei-templates. Its existence raises the odds of exploitation; it does not confirm attacks.
Description
Barracuda Email Security Gateway (ESG) appliance contains an improper input validation vulnerability of a user-supplied .tar file, leading to remote command injection.
Weaknesses
- CWE-20Improper Input Validation (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #18OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.