CVE-2017-17704
There is no authentication of messages beyond the use of the fixed AES key, so message forgery is also possible.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.99%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A door-unlocking issue was discovered on Software House iStar Ultra devices through 6.5.2.20569 when used in conjunction with the IP-ACM Ethernet Door Module. The communications between the IP-ACM and the iStar Ultra is encrypted using a fixed AES key and IV. Each message is encrypted in CBC mode and restarts with the fixed IV, leading to replay attacks of entire messages. There is no authentication of messages beyond the use of the fixed AES key, so message forgery is also possible.
- CVSS 3.0
- 7.4 HIGHCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H
- EPSS
- 0.99% probability · 62th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-330
- Affected
- swhouse/istar ultra firmware
- Source
- cve@mitre.org
EPSS 1.0% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.