What is CVE-2017-17704?

CVE-2017-17704 is a high-severity vulnerability in Swhouse Istar Ultra, classified under Use of Insufficiently Random Values. CVSS score: 7.4/10. Published 2017-12-31.

How severe is CVE-2017-17704?

High severity. CVSS v3 base score is 7.4 out of 10.

Vulnerability in Swhouse Istar Ultra

CVE-2017-17704

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.

Published 2017-12-31 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H.

EPSS exploit prediction

EPSS: 0.010 (62.2th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 62nd percentile — 62.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: -0.000

Affected products

Weakness classification (CWE)

CWE-330 — Use of Insufficiently Random Values

References

systemoverlord.com/2017/12/18/cve-2017-17704-broken-cryptography-in-istar-ultra… (Third Party Advisory)

Frequently asked questions

What is CVE-2017-17704?: CVE-2017-17704 is a high-severity vulnerability in Swhouse Istar Ultra, classified under Use of Insufficiently Random Values. CVSS score: 7.4/10. Published 2017-12-31.
How severe is CVE-2017-17704?: High severity. CVSS v3 base score is 7.4 out of 10.