SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2015-5600

The kbdint_next_device function in auth2-chall.c in sshd in OpenSSH through 6.9 does not properly restrict the processing of keyboard-interactive devices within a single connection, which makes it easier for remote attackers to conduct brute-force…

HIGH 8.1EPSS 9.38%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (9.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

The kbdint_next_device function in auth2-chall.c in sshd in OpenSSH through 6.9 does not properly restrict the processing of keyboard-interactive devices within a single connection, which makes it easier for remote attackers to conduct brute-force attacks or cause a denial of service (CPU consumption) via a long and duplicative list in the ssh -oKbdInteractiveDevices option, as demonstrated by a modified client that provides a different password for each pam element on this list.

CVSS 3.1
8.1 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
9.38% probability · 95th percentile
CISA KEV
Not listed
Weakness
CWE-264, CWE-400
Affected
openbsd/openssh
Source
cve@mitre.org

References

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