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CVE-2023-6654

MEDIUM

CVE-2023-6654 is a medium-severity (CVSS 6.3) Deserialization of Untrusted Data vulnerability in phpems phpems. O3 Security detects and blocks CVE-2023-6654 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.

A vulnerability classified as critical was found in PHPEMS 6.x/7.x/8.x/9.0. Affected by this vulnerability is an unknown functionality in the library lib/session.cls.php of the component…

Published
Dec 10, 2023
Updated
Jun 17, 2026
Affected
1 product
Patched
See advisory
Exploits
None indexed

Description

A vulnerability classified as critical was found in PHPEMS 6.x/7.x/8.x/9.0. Affected by this vulnerability is an unknown functionality in the library lib/session.cls.php of the component Session Data Handler. The manipulation leads to deserialization. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The identifier VDB-247357 was assigned to this vulnerability.

Affected Products

1 product · 2 configurations
Application
phpemsphpems
2 versions
6.07.0

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every phpems phpems deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for remote code execution at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Remediation status

    No patch has shipped for CVE-2023-6654 yet — track the phpems phpems advisory for a fixed release and apply the workarounds below in the meantime.

  3. Mitigate without a patch

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2023-6654 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2023-6654. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

A vulnerability classified as critical was found in PHPEMS 6.x/7.x/8.x/9.0. Affected by this vulnerability is an unknown functionality in the library lib/session.cls.php of the component Session Data Handler. The manipulation leads to deserialization. The attack can be launched remotely. The exploit has been disclosed to the public and may be used. The identifier VDB-247357 was assigned to this vulnerability.
O3 Security · Runtime Protection

Is CVE-2023-6654 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2023-6654 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.