VulnerabilityModified

CVE-2017-17704

There is no authentication of messages beyond the use of the fixed AES key, so message forgery is also possible.

HIGH 7.4EPSS 1.00%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.00%). 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: 1.00% probability · 61th percentile
CISA KEV: Not listed
Weakness: CWE-330
Affected: swhouse/istar ultra firmware
Source: cve@mitre.org

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.