Detections
Analytics
FreeBSD : openssh -- multiple vulnerabilities (32db37a5-50c3-11db-acf3-000c6ec775d9)
high Nessus Plugin ID 22488
Synopsis
The remote FreeBSD host is missing one or more security-related updates.Description
Problem Description The CRC compensation attack detector in the sshd(8) daemon, upon receipt of duplicate blocks, uses CPU time cubic in the number of duplicate blocks received. [CVE-2006-4924]A race condition exists in a signal handler used by the sshd(8) daemon to handle the LoginGraceTime option, which can potentially cause some cleanup routines to be executed multiple times. [CVE-2006-5051] Impact An attacker sending specially crafted packets to sshd(8) can cause a Denial of Service by using 100% of CPU time until a connection timeout occurs. Since this attack can be performed over multiple connections simultaneously, it is possible to cause up to MaxStartups (10 by default) sshd processes to use all the CPU time they can obtain.
[CVE-2006-4924]
The OpenSSH project believe that the race condition can lead to a Denial of Service or potentially remote code execution, but the FreeBSD Security Team has been unable to verify the exact impact.
[CVE-2006-5051] Workaround The attack against the CRC compensation attack detector can be avoided by disabling SSH Protocol version 1 support in sshd_config(5).
There is no workaround for the second issue.
Solution
Update the affected packages.See Also
Plugin Details
Severity: High
ID: 22488
File Name: freebsd_pkg_32db37a550c311dbacf3000c6ec775d9.nasl
Version: 1.20
Type: local
Family: FreeBSD Local Security Checks
Published: 10/2/2006
Updated: 1/6/2021
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 6.7
CVSS v2
Risk Factor: High
Base Score: 9.3
Temporal Score: 7.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C
Vulnerability Information
CPE: p-cpe:/a:freebsd:freebsd:openssh, p-cpe:/a:freebsd:freebsd:openssh-portable, cpe:/o:freebsd:freebsd
Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info
Exploit Available: true
Exploit Ease: Exploits are available
Patch Publication Date: 9/30/2006
Vulnerability Publication Date: 9/25/2006
Reference Information
CVE: CVE-2006-4924, CVE-2006-5051