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CISA KEV·Added 2023-05-26 — agencies required to remediate by 2023-06-16

CVE-2023-2868

CRITICAL

A remote command injection vulnerability exists in the Barracuda Email Security Gateway (appliance form factor only) product effecting versions 5.1.3.001-9.2.0.006. The vulnerability…

Published
May 24, 2023
Updated
Jun 17, 2026
Affected
0 pkgs
Patched
None yet
Exploits
4 known

EPSS Exploitation Probability

via FIRST.org ↗
87.0%probability of exploitation in next 30 days
Very High Risk100th percentile0.00%
85.8%87.9%89.9%91.9%90.3%87.0%Jan 26May 26Jul 26

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

A remote command injection vulnerability exists in the Barracuda Email Security Gateway (appliance form factor only) product effecting versions 5.1.3.001-9.2.0.006. The vulnerability arises out of a failure to comprehensively sanitize the processing of .tar file (tape archives). The vulnerability stems from incomplete input validation of a user-supplied .tar file as it pertains to the names of the files contained within the archive. As a consequence, a remote attacker can specifically format these file names in a particular manner that will result in remotely executing a system command through Perl's qx operator with the privileges of the Email Security Gateway product. This issue was fixed as part of BNSF-36456 patch. This patch was automatically applied to all customer appliances.

Affected Products

5 products · 5 configurations
OS
email security gateway 300 firmwarebarracuda
≥ 5.1.3.001 && ≤ 9.2.0.006
range
OS
email security gateway 400 firmwarebarracuda
≥ 5.1.3.001 && ≤ 9.2.0.006
range
OS
email security gateway 600 firmwarebarracuda
≥ 5.1.3.001 && ≤ 9.2.0.006
range
OS
email security gateway 800 firmwarebarracuda
≥ 5.1.3.001 && ≤ 9.2.0.006
range
OS
email security gateway 900 firmwarebarracuda
≥ 5.1.3.001 && ≤ 9.2.0.006
range
Exploits & PoCs
4

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every barracuda email security gateway 300 firmware deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Remediation status

    No patch has shipped for CVE-2023-2868 yet — track the barracuda email security gateway 300 firmware advisory for a fixed release and apply the workarounds below in the meantime.

  3. Mitigate without a patch

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2023-2868 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2023-2868. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

A remote command injection vulnerability exists in the Barracuda Email Security Gateway (appliance form factor only) product effecting versions 5.1.3.001-9.2.0.006. The vulnerability arises out of a failure to comprehensively sanitize the processing of .tar file (tape archives). The vulnerability stems from incomplete input validation of a user-supplied .tar file as it pertains to the names of the files contained within the archive. As a consequence, a remote attacker can specifically format these file names in a particular manner that will result in remotely executing a system command through
O3 Security · Runtime Protection

Is CVE-2023-2868 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2023-2868 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.