CVE-2009-1959

irssi 0.8.13 - Denial of Service via Empty IRC Command

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2009-1959. PoCs published by nemo.

AI-analyzed exploit summary The provided text describes an off-by-one heap-based memory corruption vulnerability in Irssi 0.8.13, which can lead to a denial-of-service or potential arbitrary code execution. The example IRC command ': WALLOPS \001ACTION' is given as a trigger for the vulnerability.

Description

Off-by-one error in the event_wallops function in fe-common/irc/fe-events.c in irssi 0.8.13 allows remote IRC servers to cause a denial of service (crash) via an empty command, which triggers a one-byte buffer under-read and a one-byte buffer underflow.

Exploits (1)

exploitdb WRITEUP VERIFIED
by nemo · textdoslinux
https://www.exploit-db.com/exploits/33041

The provided text describes an off-by-one heap-based memory corruption vulnerability in Irssi 0.8.13, which can lead to a denial-of-service or potential arbitrary code execution. The example IRC command ': WALLOPS \001ACTION' is given as a trigger for the vulnerability.

Classification
Writeup 80%
Attack Type
Dos
Complexity
Trivial
Reliability
Theoretical
Target: Irssi 0.8.13
No auth needed
Prerequisites: Access to an IRC network where the vulnerable Irssi client is connected
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (15)

Core 15
Core References
Third Party Advisory, VDB Entry vdb-entry x_refsource_sectrack
http://www.securitytracker.com/id?1022410
Mailing List mailing-list x_refsource_mlist
http://www.openwall.com/lists/oss-security/2009/05/29/3
Third Party Advisory, VDB Entry vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/35399
Exploit, Vendor Advisory x_refsource_confirm
http://www.irssi.org/ChangeLog
Exploit, Vendor Advisory x_refsource_confirm
http://bugs.irssi.org/index.php?do=details&task_id=662
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/35685
Third Party Advisory vdb-entry x_refsource_vupen
http://www.vupen.com/english/advisories/2009/1596
Vendor Advisory vendor-advisory x_refsource_ubuntu
http://www.ubuntu.com/usn/usn-800-1
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/35812
Vendor Advisory vendor-advisory x_refsource_mandriva
http://www.mandriva.com/security/advisories?name=MDVSA-2009:133
Third Party Advisory, VDB Entry vdb-entry x_refsource_xf
https://exchange.xforce.ibmcloud.com/vulnerabilities/51184
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/36152

Scores

EPSS 0.0838
EPSS Percentile 94.3%

Details

CWE
CWE-189
Status published
Products (1)
irssi/irssi 0.8.13
Published Jun 08, 2009
Tracked Since Feb 18, 2026