Exploited

CVE-2023-2868

Barracuda Networks Email Security Gateway (ESG) · Email

Barracuda Networks ESG Appliance Improper Input Validation Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on May 26, 2023.

Affected product: Barracuda Networks Email Security Gateway (ESG) (category Email, indicative classification). Name in CISA’s catalog: Barracuda Networks Email Security Gateway (ESG) Appliance.

What should I do?

Apply the security update from Barracuda Networks.

Deadline set by CISA for US federal agencies: 21 days (due June 16, 2023). It only binds those agencies, but it is a useful measure of urgency.

The vendor’s specific advisory is listed in the NVD references: CVE-2023-2868 on the NVD website.

Original text of the required action (CISA)

Apply updates per vendor instructions.

Timeline

May 24, 2023 Vulnerability published Publication date (NVD)
May 26, 2023 Exploitation confirmed Added to CISA’s KEV catalog
June 16, 2023 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on May 26, 2023 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Apply the security update from Barracuda Networks. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: June 16, 2023, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: May 24, 2023 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: Barracuda Networks Email Security Gateway (ESG) Appliance Filed by this site under “Email” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

9.8 / 10 CVSS severity: critical

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

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.

Barracuda Email Security Gateway (ESG) appliance contains an improper input validation vulnerability of a user-supplied .tar file, leading to remote command injection.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).