Siemens ACC-AP Firmware Signature Verification Flaw
🔒 Siemens' Building X - Security Manager Edge Controller (ACC-AP) contains an improper verification of cryptographic signature in its firmware update process that could permit installation of maliciously modified firmware. Tracked as CVE-2022-31807 and affecting all ACC-AP versions, the flaw may be exploited by a local attacker or by an adversary able to intercept firmware transfers. Siemens reports no planned fix for this product; operators should use the ACC Firmware App, validate firmware hashes, restrict controller access, and isolate devices from untrusted networks as compensating controls.
