Libraesva has launched a security replace to deal with a vulnerability in its Electronic mail Safety Gateway (ESG) resolution that it stated has been exploited by state-sponsored risk actors.
The vulnerability, tracked as CVE-2025-59689, carries a CVSS rating of 6.1, indicating medium severity.
“Libraesva ESG is affected by a command injection flaw that may be triggered by a malicious e-mail containing a specifically crafted compressed attachment, permitting potential execution of arbitrary instructions as a non-privileged person,” Libraesva stated in an advisory.
“This happens because of an improper sanitization throughout the elimination of lively code from recordsdata contained in some compressed archive codecs.”
In a hypothetical assault state of affairs, an attacker may exploit the flaw by sending an e-mail containing a specifically crafted compressed archive, permitting a risk actor to leverage the appliance’s improper sanitization logic to finally execute arbitrary shell instructions.
The shortcoming impacts Libraesva ESG variations 4.5 by 5.5.x earlier than 5.5.7, with fixes launched in 5.0.31, 5.1.20, 5.2.31, 5.3.16, 5.4.8, and 5.5.7. Libraesva famous within the alert that variations beneath 5.0 have reached end-of-support and should be manually upgraded to a supported launch.
The Italian e-mail security firm additionally acknowledged that it has recognized one confirmed incident of abuse, and that the risk actor is “believed to be a international hostile state entity.” It didn’t share any additional particulars on the character of the exercise, or who could also be behind it.
“The only‑equipment focus underscores the precision of the risk actor (believed to be a international hostile state) and highlights the significance of fast, complete patch deployment,” Libraesva stated, including it deployed a repair inside 17 hours of flagging the abuse.
In gentle of lively exploitation, it is important that customers of the ESG software program replace their situations to the most recent model as quickly as potential to mitigate potential threats.
