# CVE-1999-1296: MIT Kerberos buffer overflow in Kerberos IV compatibility library

Source: https://junglewise.ai/threats/cve-1999-1296-mit-kerberos-buffer-overflow-in-kerberos-iv-compatibility-library  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 1997-04-29. Updated: 2026-05-10  
License: CC BY 4.0 with a link back

CVE-1999-1296 · Severity: high · CVSS 7.2 · Published 1997-04-29

A vulnerability in the Kerberos authentication system allows local users to gain full administrative (root) control over a computer. Kerberos is a widely used service for verifying user identities across a network. By manipulating a specific configuration setting, a standard user can trigger a memory error that grants them elevated privileges, potentially leading to unauthorized access to sensitive data or system-wide disruption.

Technologies: [Mit Kerberos 5](https://junglewise.ai/threats/technologies/kerberos-5), [Openbsd](https://junglewise.ai/threats/technologies/openbsd). Vendors: [Mit](https://junglewise.ai/threats/vendors/mit), [OpenBSD](https://junglewise.ai/threats/vendors/openbsd).

## Quick answers

**Is CVE-1999-1296 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-1999-1296 being exploited in the wild.

**How severe is CVE-1999-1296?** High severity, with a CVSS score of 7.2, published 29 April 1997.

**Which products and versions are affected?** Cygnus Kerberos 4 (Bones) R3; Mit Kerberos 4 compatibility library 1.0; Openbsd 2.0.

**Is there a fix for CVE-1999-1296?** 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-1999-1296 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-1999-1296?** Check whether you run Cygnus Kerberos 4 (Bones), Mit Kerberos 4 compatibility library, Mit Kerberos 5 or one of the others listed at an affected version. 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

A buffer overflow exists in the Kerberos IV compatibility library (specifically within src/lib/krb4/g_krbhst.c) due to insufficient bounds checking when reading configuration files. The vulnerability is triggered when the krb_get_krbhst function uses fscanf to read from a file specified by the KRB_CONF environment variable into a fixed-size buffer (linebuf). A local attacker can exploit this by pointing the environment variable to a malicious configuration file containing an excessively long line. If a setuid or setgid program (such as a Kerberized rlogin) utilizes these library functions, the attacker can overwrite the stack and execute arbitrary code with root privileges. This issue affects MIT Kerberos V 1.0, KTH 0.9.3, OpenBSD 2.0, and Cygnus R3 distributions.

## Affected products

- MIT Kerberos 5 1.0
- MIT Kerberos 4 compatibility library 1.0
- KTH KTH Kerberos 4 0.9.3
- OpenBSD OpenBSD 2.0
- Cygnus Cygnus Kerberos 4 (Bones) R3

## Timeline

- 1997-04-29: disclosed: Advisory released by Secure Networks Inc.
- 1997-04-29: advisory: NVD publication date

## References

- [http://marc.info/?l=bugtraq&m=87602167420878&w=2](http://marc.info/?l=bugtraq&m=87602167420878&w=2)

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