CISA adds recently patched Barracuda zero-day to its Known Exploited Vulnerabilities catalog
Vulnerabilities mentionedAll →
| CVE | Vulnerability | CVSS | EPSS | Flags | Affected | Exposure | Published |
|---|---|---|---|---|---|---|---|
| CVE-2023-2868 | Unauthenticated Command Injection in Barracuda Email Security Gateway Appliances via .tar Files CVE-2023-2868 is a critical (CVSS 9.8) remote command injection vulnerability in the Barracuda Email Security Gateway (ESG) appliance form factor (models 300, 400, 600, 800 and 900), caused by incomplete input validation of user-supplied .tar archives, specifically the names of the files contained within them. An attacker can deliver a specially crafted .tar file whose internal file names are formatted so that, when the ESG processes the archive, commands are executed through Perl's qx operator. Successful exploitation yields remote command execution with the privileges of the ESG product, and in the observed campaign attackers deployed a backdoor (reported as "SUBMARINE") and persisted on compromised appliances. Only customers running ESG appliances on versions 5.1.3.001 through 9.2.0.006 are affected. Exploitation is confirmed in the wild — CISA added it to the KEV on 2023-05-26, EPSS puts 30-day exploitation probability at 87.7%, and public reporting attributes active exploitation to a Chinese-nexus espionage group (associated in headlines with Salt Typhoon) targeting government, military, and telecom victims; Barracuda's BNSF-36456 patch was applied automatically to customer appliances. Do: Verify that each ESG appliance received the automatic BNSF-36456 patch (running fixed firmware at or above 9.2.0.006's successor per vendor instructions), and check appliances for indicators of compromise, including unauthorized command activity and the "SUBMARINE" backdoor, using Barracuda's IOC guidance. Because the espionage campaign established persistence, Barracuda urged full replacement rather than patching of compromised appliances; replace any ESG showing signs of compromise and review email logs for malicious .tar attachments. Limit or monitor internet exposure of ESG management interfaces while remediation proceeds. | 9.8 | 88% | KEV |
| largetens of thousands of deployed ESG appliances (public scans show Barracuda ESGs among commonly internet-exposed email security devices); Barracuda's incident… |
Full article331 words · extracted from securityaffairs.com · click to collapse

US CISA added recently patched Barracuda zero-day vulnerability to its Known Exploited Vulnerabilities catalog.
US Cybersecurity and Infrastructure Security Agency (CISA) added a recently patched Barracuda zero-day vulnerability to its Known Exploited Vulnerabilities Catalog.
This week, the network security solutions provider Barracuda warned customers that some of its Email Security Gateway (ESG) appliances were recently breached by threat actors exploiting a now-patched zero-day vulnerability.
The vulnerability, tracked as CVE-2023-2868, resides in the module for email attachment screening, the issue was discovered on May 19 and the company fixed it with the release of two security patches on May 20 and 21.
“Barracuda identified a vulnerability (https://nvd.nist.gov/vuln/detail/CVE-2023-2868) in our Email Security Gateway appliance (ESG) on May 19, 2023. A security patch to eliminate the vulnerability was applied to all ESG appliances worldwide on Saturday, May 20, 2023.” reads the advisory published by the security solutions provider. “The vulnerability existed in a module which initially screens the attachments of incoming emails.”
The issue could have a significant impact because the impacted Email Security Gateway (ESG) appliances are used by hundreds of thousands of organizations worldwide, including several high-profile businesses.
The vulnerability doesn’t impact other Barracuda products, the company states that its SaaS email security services is not affected by this issue.
The company investigated the flaw and discovered that it was exploited to target a subset of email gateway appliances. The company notified via the ESG user interface the customers whose appliances they believe were impacted.
According to Binding Operational Directive (BOD) 22-01: Reducing the Significant Risk of Known Exploited Vulnerabilities, FCEB agencies have to address the identified vulnerabilities by the due date to protect their networks against attacks exploiting the flaws in the catalog.
Experts recommend also private organizations review the Catalog and address the vulnerabilities in their infrastructure.
CISA orders federal agencies to fix this flaw by June 16, 2023.
Follow me on Twitter: @securityaffairs and Facebook and Mastodon
(SecurityAffairs – hacking, CISA)
Text extracted automatically; images, tables and formatting may be missing. Original: https://securityaffairs.com/146729/security/cisa-barracuda-0day-catalog.html