What is the CVSS score of CVE-2026-36829?

CVE-2026-36829 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.4%.

Which versions of Panabit PAP-XM320 are affected by CVE-2026-36829?

Panabit PAP-XM320 network appliances (v7.7 and earlier) contain a critical authentication bypass vulnerability allowing remote unauthenticated attackers to gain full administrative access.

How to fix or mitigate CVE-2026-36829?

Within 24 hours, identify all Panabit PAP-XM320 devices in production, document their network roles and data access, and assess whether they are internet-facing or accessible from untrusted networks. Within 7 days, implement network segmentation to restrict management interface access to trusted IP ranges only, deploy Web Application Firewall rules to block directory traversal patterns in HTTP cookies, and disable the embedded HTTP server if alternative management methods exist. Within 30 days, contact Panabit for patch availability and timeline, establish continuous monitoring for exploitation attempts via logs and network telemetry, and evaluate replacement appliances or architectural alternatives that do not depend on this vulnerable component.

Panabit PAP-XM320 CVE-2026-36829

EUVD-2026-30953 CRITICAL

Path Traversal (CWE-22)

2026-05-19 mitre

GHSA-xh8m-w9h2-4fc7

Authentication Bypass Path Traversal N A

9.8

CVSS 3.1 · Vendor: mitre

Severity by source

Vendor (mitre) PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

vuln.today AI

9.8 CRITICAL

Remote unauthenticated cookie traversal bypasses authentication with low complexity, yielding full admin control over the device, so AV:N/AC:L/PR:N and C/I/A all High.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Primary rating from Vendor (mitre).

CVSS VectorVendor: mitre

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Jul 23, 2026 - 17:58 vuln.today

CVE Published

May 19, 2026 - 00:00 cve.org

CRITICAL 9.8

CVE Published

May 19, 2026 - 00:00 nvd

UNKNOWN (no severity yet)

DescriptionCVE.org

An authentication bypass vulnerability exists in the embedded HTTP server of Panabit PAP-XM320 up to and including v7.7. The server validates session cookies using a filesystem existence check based on a user-controlled cookie value without proper sanitization, allowing directory traversal and bypass of authentication.

AnalysisAI

Authentication bypass in the embedded HTTP server of Panabit PAP-XM320 (versions up to and including v7.7) lets remote unauthenticated attackers gain administrative access by supplying a crafted session cookie. The server validates sessions with a filesystem existence check against the unsanitized cookie value, so directory traversal in that value satisfies the check and defeats authentication. SSVC rates technical impact as total and the attack as automatable, and publicly available exploit code exists, though EPSS remains modest at 0.43%.

Technical ContextAI

The affected component is the web management interface (embedded HTTP server) of Panabit's PAP-XM320, a network/bandwidth-management appliance. The root cause is CWE-22 (Improper Limitation of a Pathname to a Restricted Directory / Path Traversal): the server authenticates a request by treating the client-supplied session cookie as part of a filesystem path and testing whether a corresponding session file exists, without canonicalizing or sanitizing the value. Because traversal sequences (e.g. ../) are not stripped, an attacker can steer the existence check toward a path guaranteed to exist, causing the server to conclude a valid session is present. This conflates 'a file exists on disk' with 'this user is authenticated,' a classic path-traversal-driven access-control failure.

RemediationAI

No vendor-released patch or fixed version is identified in the available data, so a specific upgrade target cannot be cited (absence of data, not confirmation that none exists). As compensating controls, restrict network access to the PAP-XM320 management HTTP server to a dedicated management VLAN or trusted admin hosts via firewall/ACL so the vulnerable endpoint is not reachable from untrusted or Internet-facing networks (trade-off: administrators must then connect through the management network or VPN); disable or firewall off remote web administration if the interface is not required for daily operations; and monitor web-server logs for cookie values containing traversal sequences (e.g. ../ or encoded variants) as an indicator of exploitation. Consult the vendor at https://www.panabit.com/ and the technical write-up at https://secreu.notion.site/CVE-2026-36829-3652c0ab461580e19704e87b18865714 for an official fix, and apply a vendor patch as soon as one is published.