CVE-2002-0839

Severity: high (CVSS 7.2 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2002-10-11 · updated 2026-06-16

Description

The shared memory scoreboard in the HTTP daemon for Apache 1.3.x before 1.3.27 allows any user running as the Apache UID to send a SIGUSR1 signal to any process as root, resulting in a denial of service (process kill) or possibly other behaviors that would not normally be allowed, by modifying the parent[].pid and parent[].last_rtime segments in the scoreboard.

Affected products

Apache HTTP Server: from 1.3.0 before 1.3.27 — fixed in 1.3.27
Debian Linux: 2.2, 3.0

How to fix

Upgrade to a fixed version: Apache HTTP Server 1.3.27. Check the vendor advisory for mitigations.

References

http://archives.neohapsis.com/archives/bugtraq/2002-10/0195.html
http://archives.neohapsis.com/archives/bugtraq/2002-10/0254.html
http://archives.neohapsis.com/archives/vulnwatch/2002-q4/0012.html
http://distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000530
http://marc.info/?l=apache-httpd-announce&m=103367938230488&w=2
http://marc.info/?l=bugtraq&m=103376585508776&w=2
http://marc.info/?l=bugtraq&m=130497311408250&w=2
http://online.securityfocus.com/advisories/4617
http://www.apacheweek.com/issues/02-10-04
http://www.debian.org/security/2002/dsa-187
http://www.debian.org/security/2002/dsa-188

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