CVE-1999-0863: Buffer Overflow

Published Nov 8, 1999
·
Updated

Buffer overflow in FreeBSD seyon via HOME environmental variable, -emulator argument, -modems argument, or the GUI.

Affected Software

1 affected component
FreeBSD FreeBSD=3.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Remove

    Remove FreeBSD seyon from your environment.

    Uninstall or remove the seyon component from affected systems or otherwise prevent it from being executed until an official patch/fix is available.

  2. Configuration

    Ensure the HOME environment variable is sanitized or cleared before launching seyon (for example, run seyon from a wrapper that unsets or sets HOME to a safe value).

    seyon HOME environment variable handling = sanitize/clear
  3. Configuration

    Prevent use of the -emulator and -modems command-line arguments (for example, use a wrapper to strip/validate arguments or configure invocation to avoid these arguments) until a patch is available.

    seyon command-line arguments (-emulator, -modems) = do not accept/use
  4. Configuration

    Disable or avoid using the seyon graphical interface (GUI) until an official fix is released.

    seyon GUI GUI enabled = false
  5. Compensating control

    Restrict execution of the seyon binary to trusted administrative accounts (file permissions, exec ACLs) and prevent untrusted users from invoking it; monitor and block attempts to run seyon from untrusted contexts.

Event History

Nov 8, 1999
CVE Published
05:00 AM
Data Sourced
via NVD·05:00 AM
DescriptionSeverityAffected Software
Feb 4, 2000
CVE Published
via MITRE·10:00 AM
Data Sourced
via MITRE·10:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-1999-0863?

CVE-1999-0863 is considered a critical vulnerability due to its potential to allow arbitrary code execution via a buffer overflow.

2

How do I fix CVE-1999-0863?

To fix CVE-1999-0863, users should upgrade to a patched version of FreeBSD that addresses this vulnerability.

3

What systems are affected by CVE-1999-0863?

CVE-1999-0863 specifically affects FreeBSD version 3.3.

4

Can CVE-1999-0863 be exploited remotely?

Yes, CVE-1999-0863 can be exploited remotely if the vulnerable software is exposed to untrusted users.

5

What are the potential impacts of CVE-1999-0863?

The potential impacts of CVE-1999-0863 include system crashes and unauthorized remote code execution.

Contact

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