Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Email Gateway and Cisco Secure Email and Web Manager engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76440 are related to path traversal issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-23.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "9.8",
  "pubDate": "2026-09-14T17:17:50.520Z",
  "pubdate": "2026-09-14T17:17:50.520Z",
  "executiveSummary": "Cisco Secure Email Gateway and Cisco Secure Email and Web Manager are susceptible to path traversal vulnerabilities, identified as CVE-2026-76440.\nCategorized under CWE-23, these vulnerabilities arise from inadequate validation of user-supplied input used to construct file system paths.\nAn unauthenticated or authenticated attacker (depending on the specific interface exposure) could potentially exploit these flaws to read, modify, or delete sensitive files outside of the intended directory structure.\nThe successful exploitation of this path traversal vulnerability poses significant security risks, including unauthorized access to configuration files, system credentials, or internal application data.\nBecause the vulnerabilities were identified during an internal security review, Cisco has released software hardening updates to remediate these flaws.\nOrganizations are advised to prioritize the application of the provided software updates to prevent potential compromise of the appliance integrity.",
  "technicalDetails": "CVE-2026-76440 pertains to path traversal vulnerabilities (CWE-23) discovered within the Cisco Secure Email Gateway and Cisco Secure Email and Web Manager platforms. These vulnerabilities stem from the improper sanitization or validation of input paths provided to the file system interface within the appliance software.\nThe root cause is a failure to effectively neutralize input containing directory traversal sequences, such as '../' (dot-dot-slash) or encoded variants, which are processed by the application when interacting with the underlying file system. When the application uses this untrusted input to construct file paths for reading or writing operations, an attacker can manipulate the path to escape the root directory intended for such operations.\nIn a typical attack flow, an adversary crafts a malicious request targeting an interface that handles file operations. By including traversal sequences in the input parameters, the attacker forces the application to resolve a path that leads to arbitrary files on the system outside of the restricted directory. This allows the attacker to bypass access control mechanisms enforced by the application's logical directory structure.\nThe vulnerability allows for unauthorized file system interaction. Depending on the specific implementation of the vulnerable component, an attacker may be able to read system configuration files, sensitive application data, or potentially perform unauthorized write operations, depending on the file system permissions of the service account running the appliance software.\nThe impact includes, but is not limited to, the disclosure of sensitive information which could be used to facilitate further attacks, such as escalating privileges or gaining deeper persistence within the appliance. The vulnerability does not require complex exploitation techniques, but success is contingent on the attacker’s ability to submit input to the vulnerable component and the system's ability to resolve the manipulated path.\nAffected versions of Cisco Secure Email Gateway and Cisco Secure Email and Web Manager contain these weaknesses across various internal modules that handle file system interactions. The exposure of these interfaces to the network increases the attack surface, allowing potential exploitation if network-level controls are not sufficient to restrict access to the vulnerable endpoints."
}