CVE-2013-4559

Severity: high (CVSS 7.6 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 10.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2013-11-20 · updated 2026-06-16
Weakness: CWE-264

Description

lighttpd before 1.4.33 does not check the return value of the (1) setuid, (2) setgid, or (3) setgroups functions, which might cause lighttpd to run as root if it is restarted and allows remote attackers to gain privileges, as demonstrated by multiple calls to the clone function that cause setuid to fail when the user process limit is reached.

Affected products

Debian Linux: 6.0, 7.0, 8.0
lighttpd: before 1.4.33 — fixed in 1.4.33
Opensuse: 12.2, 12.3, 13.1

How to fix

Upgrade to a fixed version: lighttpd 1.4.33. Check the vendor advisory for mitigations.

References

http://download.lighttpd.net/lighttpd/security/lighttpd_sa_2013_02.txt
http://jvn.jp/en/jp/JVN37417423/index.html
http://lists.opensuse.org/opensuse-updates/2014-01/msg00049.html
http://marc.info/?l=bugtraq&m=141576815022399&w=2
http://secunia.com/advisories/55682
http://www.openwall.com/lists/oss-security/2013/11/12/4
https://kc.mcafee.com/corporate/index?page=content&id=SB10310
https://www.debian.org/security/2013/dsa-2795
http://download.lighttpd.net/lighttpd/security/lighttpd_sa_2013_02.txt
http://jvn.jp/en/jp/JVN37417423/index.html
http://lists.opensuse.org/opensuse-updates/2014-01/msg00049.html
http://marc.info/?l=bugtraq&m=141576815022399&w=2

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