irssi IRC client 0.8.4, when downloaded after 14-March-2002, could contain a backdoor in the configuration file, which allows remote attackers to access the system.

The official irssi docker images before 1.1-alpine (Alpine specific) contain a blank password for a root user. System using the irssi docker container deployed by affected versions of the Docker image may allow an remote attacker to achieve root access with a blank password.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. There is a use-after-free when SASL messages are received in an unexpected order.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. There is a use-after-free when a server is disconnected during netsplits. NOTE: this issue exists because of an incomplete fix for CVE-2017-7191.

Irssi 1.2.x before 1.2.2 has a use-after-free if the IRC server sends a double CAP.

When the channel topic is set without specifying a sender, Irssi before 1.0.6 may dereference a NULL pointer.

In Irssi before 1.0.6, a calculation error in the completion code could cause a heap buffer overflow when completing certain strings.

Irssi 1.1.x before 1.1.2 has a use after free when hidden lines are expired from the scroll buffer.

An issue was discovered in Irssi before 1.0.4. While updating the internal nick list, Irssi could incorrectly use the GHashTable interface and free the nick while updating it. This would then result in use-after-free conditions on each access of the hash table.

An issue was discovered in Irssi before 1.0.4. When receiving messages with invalid time stamps, Irssi would try to dereference a NULL pointer.

The netjoin processing in Irssi 1.x before 1.0.2 allows attackers to cause a denial of service (use-after-free) and possibly execute arbitrary code via unspecified vectors.

Multiple CRLF injection vulnerabilities in (1) ixmmsa.pl 0.3, (2) l33tmusic.pl 2.00, (3) mpg123.pl 0.01, (4) ogg123.pl 0.01, (5) xmms.pl 2.0, (6) xmms2.pl 1.1.3, and (7) xmmsinfo.pl 1.1.1.1 scripts for irssi before 0.8.11 allow user-assisted remote attackers to execute arbitrary IRC commands via CRLF sequences in the name of the song in a .mp3 file.

Irssi before 1.0.8, 1.1.x before 1.1.3, and 1.2.x before 1.2.1, when SASL is enabled, has a use after free when sending SASL login to the server.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. A NULL pointer dereference occurs for an "empty" nick.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. When the number of windows exceeds the available space, a crash due to a NULL pointer dereference would occur.

An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. Certain nick names could result in out-of-bounds access when printing theme strings.

When using incomplete escape codes, Irssi before 1.0.6 may access data beyond the end of the string.

When using an incomplete variable argument, Irssi before 1.0.6 may access data beyond the end of the string.

In Irssi before 1.0.5, certain incorrectly formatted DCC CTCP messages could cause a NULL pointer dereference. This is a separate, but similar, issue relative to CVE-2017-9468.

In Irssi before 1.0.5, overlong nicks or targets may result in a NULL pointer dereference while splitting the message.

Irssi before 1.0.5, while waiting for the channel synchronisation, may incorrectly fail to remove destroyed channels from the query list, resulting in use-after-free conditions when updating the state later on.

Irssi before 1.0.5, when installing themes with unterminated colour formatting sequences, may access data beyond the end of the string.

In Irssi before 1.0.3, when receiving a DCC message without source nick/host, it attempts to dereference a NULL pointer. Thus, remote IRC servers can cause a crash.

In Irssi before 1.0.3, when receiving certain incorrectly quoted DCC files, it tries to find the terminating quote one byte before the allocated memory. Thus, remote attackers might be able to cause a crash.

The nickcmp function in Irssi before 0.8.21 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via a message without a nick.

Irssi before 0.8.21 allows remote attackers to cause a denial of service (out-of-bounds read and crash) via a string containing a formatting sequence (%[) without a closing bracket (]).

Irssi 0.8.18 before 0.8.21 allows remote attackers to cause a denial of service (out-of-bounds read and crash) via vectors involving strings that are not UTF8.

Use-after-free vulnerability in Irssi before 0.8.21 allows remote attackers to cause a denial of service (crash) via an invalid nick message.

Irssi 0.8.17 before 0.8.21 allows remote attackers to cause a denial of service (out-of-bounds read and crash) via a crafted ANSI x8 color code.

The formatsendtogui function in the format parsing code in Irssi before 0.8.20 allows remote attackers to cause a denial of service (heap corruption and crash) via vectors involving the length of a string.