SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-114611

A self-signed certificate from an unrelated attacker is accepted.

CRITICAL 9.1EPSS 0.23%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.23%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

OCO-Server is a self-hosted endpoint management application for computer inventory, software deployment, and mobile device management. Prior to 1.2.3,the Apple MDM enrollment endpoint `frontend/api-mdm.php` verifies the signed enrollment-request plist with `openssl_pkcs7_verify(..., PKCS7_NOVERIFY, ...)`. `PKCS7_NOVERIFY` disables signer certificate chain and trust validation, so the signature only has to be self-consistent with whatever certificate is embedded in the PKCS#7 blob. A self-signed certificate from an unrelated attacker is accepted. Because the endpoint trusts the `SERIAL` field taken from the unverified payload, anyone who knows a registered device's serial number can sign a forged plist (`SERIAL` = victim device, attacker-chosen `UDID`) with an arbitrary self-signed certificate; POST it unauthenticated to `/api-mdm.php/profile` (Content-Type: `application/pkcs7-signature`); and receive the victim device's freshly minted MDM identity: a certificate with `CN=<serial>` issued by the server's internal MDM device CA, bundled with its private key in a PKCS#12 payload inside the returned `.mobileconfig` enrollment profile. Additionally, the victim's `mobile_device` database row is silently overwritten with the attacker-supplied `UDID` (device-record hijack). With the stolen certificate and key, the attacker can impersonate the victim device on all subsequent MDM traffic (`/checkin`, `/mdm`, `/parameters`), which authenticate callers by the certificate CN (the serial number) via `checkSignature()` in the same file. This yields control over the victim device's MDM relationship: reading its management data, replacing its push token, and disrupting or redirecting its enrollment. Version 1.2.3 fixes the issue.

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS
0.23% probability · 14th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-295
Source
security-advisories@github.com
EPSS trend
0%3%5%23 October 2026: 0.23%27 October 2026: 0.23%23 October 202627 October 2026

EPSS moved from 0.2% on 23 October 2026 to 0.2% on 27 October 2026.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.