Title: OpenSSH PAM Session Evasion Vulnerability
Severity: MODERATE
Description:
When OpenSSH is used in an environment using PAM, it may be possible for local users to evade restrictions enforced by PAM modules (such as rlimits).
OpenSSH supports the traditional 'rsh' style (no pty) of remote command execution. When remote users execute commands 'rsh' style, a pam session is not initiated for the client user after authentication.
Some systems may rely on PAM to implement system restrictions, such as resource limits on processes. This vulnerability may allow remote users to bypass these restrictions.
The OpenSSH daemon will not call the pam_open_session() libcall after authentication. No PAM modules will be loaded when the program executes. This includes any modules which might be relied upon to prevent attacks against the system (for example, by setting rlimits to prevent resource exhaustion).
This vulnerability may be benign or serious depending on the PAM modules relied upon.
Affected Products:
- Conectiva Linux 5.1.0
- Conectiva Linux 6.0.0
- FreeBSD FreeBSD 4.5.0
- FreeBSD FreeBSD 4.5.0 -RELEASE
- FreeBSD FreeBSD 4.6.0
- FreeBSD FreeBSD 4.6.0 -RELEASE
- NetBSD NetBSD 1.5.0
- NetBSD NetBSD 1.5.1
- OpenSSH OpenSSH 2.1.0
- OpenSSH OpenSSH 2.1.1
- OpenSSH OpenSSH 2.2.0
- OpenSSH OpenSSH 2.3.0
- OpenSSH OpenSSH 2.5.0
- OpenSSH OpenSSH 2.5.1
- OpenSSH OpenSSH 2.5.2
- OpenSSH OpenSSH 2.9.0
- S.u.S.E. Linux 7.0.0 alpha
- S.u.S.E. Linux 7.0.0 i386
- S.u.S.E. Linux 7.0.0 ppc
- S.u.S.E. Linux 7.0.0 sparc
- S.u.S.E. Linux 7.1.0
- S.u.S.E. Linux 7.2.0
- S.u.S.E. Linux 7.3.0
- S.u.S.E. Linux Database Server
- S.u.S.E. Linux Enterprise Server 7
- S.u.S.E. Linux Firewall on CD
- S.u.S.E. SuSE eMail Server III
References:
- OpenSSH: OpenSSH Project Homepage
Juniper Networks provides this content via a wide variety of sources and production methods. If notified of errors or omissions in the content of this page, Juniper Networks, at its discretion, will modify or remove the page or leave the content as is, depending on various factors including but not limited to the reputation and authority of the party providing the notification. Please use the contact information displayed elsewhere on this page to report any errors or omissions regarding the content on this page.
