CVE-2009-4016

Integer underflow in the clean_string function in irc_string.c in (1) IRCD-hybrid 7.2.2 and 7.2.3, (2) ircd-ratbox before 2.2.9, and (3) oftc-hybrid before 1.6.8, when flatten_links is disabled, allows remote attackers to execute arbitrary code or cause a denial of service (daemon crash) via a LINKS command.

Published: 2010-02-04 Last update: 2026-04-29 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2009-4016 is rated Moderate Risk (56.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 4.01%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2009-4016

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 5.53% 4.01% -1.52%
2 2025-03-29 4.01% 5.53% +1.52%
3 2025-03-17 — 4.01% —

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2009-4016

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2009-4016

OS Trackers for CVE-2009-4016

vendor priority summary link
debian medium CVE-2009-4016 medium priority: Debian including 1 source packages (ircd-hybrid), 4 status rows across 4 suites (bookworm, bullseye, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2009-4016
redhat critical — https://access.redhat.com/security/cve/CVE-2009-4016
ubuntu medium CVE-2009-4016 medium priority: Ubuntu including 3 source packages (ircd-hybrid, ircd-ratbox, oftc-hybrid), 72 status rows across 24 suites (artful, bionic, cosmic, dapper, hardy, intrepid, jaunty, karmic, lucid, maverick, natty, oneiric, precise, quantal, raring, saucy, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): ignored 27, released 23, DNE 20, needs-triage 2. https://ubuntu.com/security/CVE-2009-4016

Affected software / configurations for CVE-2009-4016

Vendor Product Version Raw CPE
ircd-hybrid ircd-hybrid 7.2.2 cpe:2.3:a:ircd-hybrid:ircd-hybrid:7.2.2:*:*:*:*:*:*:*
ircd-hybrid ircd-hybrid 7.2.3 cpe:2.3:a:ircd-hybrid:ircd-hybrid:7.2.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox <= 2.2.8 cpe:2.3:a:ircd-ratbox:ircd-ratbox:*:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.0:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.1.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.1.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.1.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.1.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.2.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.2.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.2.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.2.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.2.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.2.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.3.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.3.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.3.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.3.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.4:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.4:rc1:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.4:rc2:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.4.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.4.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.4.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.4.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.5 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.5:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.5.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.5.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.5.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.5.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 1.5.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:1.5.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.0:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.4:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.5 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.5:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.6 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.6:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.7 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.7:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.8 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.8:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.9 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.9:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.10 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.10:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.0.11 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.0.11:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.0:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.0:beta1:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.0:beta2:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.4:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.5 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.5:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.6 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.6:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.7 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.7:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.1.8 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.1.8:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.0:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.0:rc1:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.0:rc2:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.0 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.0:rc3:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.1 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.1:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.2 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.2:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.3 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.3:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.4 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.4:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.5 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.5:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.6 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.6:*:*:*:*:*:*:*
ircd-ratbox ircd-ratbox 2.2.7 cpe:2.3:a:ircd-ratbox:ircd-ratbox:2.2.7:*:*:*:*:*:*:*
oftc oftc-hybrid <= 1.6.7 cpe:2.3:a:oftc:oftc-hybrid:*:*:*:*:*:*:*:*
oftc oftc-hybrid 1.4.0 cpe:2.3:a:oftc:oftc-hybrid:1.4.0:*:*:*:*:*:*:*
oftc oftc-hybrid 1.4.1 cpe:2.3:a:oftc:oftc-hybrid:1.4.1:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.0 cpe:2.3:a:oftc:oftc-hybrid:1.5.0:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.1 cpe:2.3:a:oftc:oftc-hybrid:1.5.1:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.2 cpe:2.3:a:oftc:oftc-hybrid:1.5.2:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.3 cpe:2.3:a:oftc:oftc-hybrid:1.5.3:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.4 cpe:2.3:a:oftc:oftc-hybrid:1.5.4:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.5 cpe:2.3:a:oftc:oftc-hybrid:1.5.5:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.6 cpe:2.3:a:oftc:oftc-hybrid:1.5.6:*:*:*:*:*:*:*
oftc oftc-hybrid 1.5.7 cpe:2.3:a:oftc:oftc-hybrid:1.5.7:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.0 cpe:2.3:a:oftc:oftc-hybrid:1.6.0:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.1 cpe:2.3:a:oftc:oftc-hybrid:1.6.1:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.2 cpe:2.3:a:oftc:oftc-hybrid:1.6.2:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.3 cpe:2.3:a:oftc:oftc-hybrid:1.6.3:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.4 cpe:2.3:a:oftc:oftc-hybrid:1.6.4:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.5 cpe:2.3:a:oftc:oftc-hybrid:1.6.5:*:*:*:*:*:*:*
oftc oftc-hybrid 1.6.6 cpe:2.3:a:oftc:oftc-hybrid:1.6.6:*:*:*:*:*:*:*

References for CVE-2009-4016

cvelogic Threat Intelligence