CVE-1999-1210: Digital UNIX xterm arbitrary file overwrite via core dump symlink

CVE-1999-1210 · Severity: high · CVSS 7.2 · Published 1997-11-12

A vulnerability in the xterm terminal emulator on Digital UNIX 4.0B allows local users to overwrite critical system files. By manipulating environment variables to force the application to crash, a user can redirect the resulting error data (core dump) to overwrite sensitive files like the password database. This can lead to a complete system failure or allow an attacker to gain administrative control.

Technologies: Digital Equipment Corporation Digital Unix. Vendors: Digital Equipment Corporation.

Quick answers

Is CVE-1999-1210 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-1999-1210 being exploited in the wild.
How severe is CVE-1999-1210?
High severity, with a CVSS score of 7.2, published 12 November 1997.
Which products and versions are affected?
Digital Equipment Corporation (DEC) Digital UNIX 4.0B with patch kit 5.
Is there a fix for CVE-1999-1210?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-1999-1210 attacked?
It is attacked with local access, in an operating system.
Am I affected by CVE-1999-1210?
Check whether you run Digital Equipment Corporation Digital Unix. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The xterm executable in Digital UNIX 4.0B (specifically after applying patch kit 5) is installed with setuid root privileges and is vulnerable to a symlink-based file overwrite. When the DISPLAY environment variable is set to an unreachable or invalid address, xterm triggers a segmentation fault during the XtOpenApplication() call. Because the process is running with elevated privileges, it may write a core dump file to the current directory. An attacker can create a symbolic link named 'core' in the working directory pointing to a sensitive system file (e.g., /etc/passwd or /vmunix), causing xterm to overwrite that file with core dump data upon crashing.

Affected products

  • Digital Equipment Corporation (DEC) Digital UNIX 4.0B with patch kit 5

Timeline

  • 1997-11-12: disclosed: Public disclosure on Bugtraq mailing list
  • 1997-11-12: advisory: NVD publication date

References

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