Quick answers
- Is CVE-2026-81939 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-81939 being exploited in the wild.
- How severe is CVE-2026-81939?
- Critical severity, with a CVSS score of 9.1, published 4 September 2026.
- Which products and versions are affected?
- SonicWall Network Security Manager On-Prem.
- Is there a fix for CVE-2026-81939?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-81939 attacked?
- It is attacked over the network, in a network appliance.
- Am I affected by CVE-2026-81939?
- Check whether you run SonicWall Network Security Manager On-Prem. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
This is a zip slip vulnerability (CWE-22) in the archive extraction logic of NSM On-Prem's file upload functionality. An attacker can craft a malicious archive file with path traversal sequences (e.g., "../../../") in filenames that, when extracted, bypass intended directory restrictions and write files to arbitrary locations on the file system. The vulnerability is triggered during file upload and archive processing operations. Successful exploitation could allow an attacker to overwrite system files, inject code, or gain unauthorized access to the system. Patches are expected to be available through SonicWall's PSIRT advisory.
Affected products
- SonicWall Network Security Manager On-Prem
Timeline
- 2026-09-04: disclosed