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OpenSSH allows arbitrary file deletion via symlink redirection of temporary file

Vulnerability Note VU#655259

Original Release Date: 2001-08-21 | Last Revised: 2001-11-15

Overview

Due to insecure handling of temporary files, some versions of sshd, an encrypted connection program, can delete any file named "cookies" accessible via the computer running sshd.

Description

sshd is the server software used to support ssh, a popular encryted connection program. Some versions of OpenSSH fail to handle temporary files in a secure fashion, allowing their removal during an ssh session. This removal may be reflected in the removal of files named "cookies" on the server. Since sshd runs setuid root, ownership and protection of the "cookies" file will be disregarded.

Impact

Using this exploit, an attacker may cause loss of data, particularly web location data used in many web sites.

Solution

Apply vendor patches; see the Systems Affected section below.

Vendor Information

655259
Expand all

Caldera

Notified:  July 03, 2001 Updated:  August 09, 2001

Status

  Vulnerable

Vendor Statement

http://www.caldera.com/support/security/advisories/CSSA-2001-023.0.txt

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

Conectiva

Notified:  June 04, 2001 Updated:  November 15, 2001

Status

  Vulnerable

Vendor Statement

http://www.linuxsecurity.com/advisories/other_advisory-1666.html

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

Immunix

Notified:  June 04, 2001 Updated:  November 15, 2001

Status

  Vulnerable

Vendor Statement

http://www.linuxsecurity.com/advisories/other_advisory-1654.html

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

NetBSD

Updated:  July 31, 2001

Status

  Vulnerable

Vendor Statement

ftp://ftp.netbsd.org/pub/NetBSD/security/advisories/NetBSD-SA2001-010.txt.asc

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

OpenBSD

Notified:  June 12, 2001 Updated:  August 21, 2001

Status

  Vulnerable

Vendor Statement

http://www.openbsd.org/errata.html#sshcookie

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

The CERT/CC has no additional comments at this time.

If you have feedback, comments, or additional information about this vulnerability, please send us email.

OpenSSH

Notified:  June 12, 2001 Updated:  August 21, 2001

Status

  Vulnerable

Vendor Statement

http://www.openbsd.org/errata.html#sshcookie

Vendor Information

The vendor has not provided us with any further information regarding this vulnerability.

Addendum

A patch to fix this problem is available at

ftp://ftp.openbsd.org/pub/OpenBSD/patches/2.9/common/006_sshcookie.patch

If you have feedback, comments, or additional information about this vulnerability, please send us email.


CVSS Metrics

Group Score Vector
Base N/A N/A
Temporal N/A N/A
Environmental N/A

References

Credit

This vulnerability was initially reported on the Bugtraq discussion list.

This document was last modified by Tim Shimeall.

Other Information

CVE IDs: CVE-2001-0529
Severity Metric: 0.76
Date Public: 2001-06-12
Date First Published: 2001-08-21
Date Last Updated: 2001-11-15 16:59 UTC
Document Revision: 11

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