The buf.pl script before 2.20 in Irssi before 0.8.20 uses weak permissions for the scrollbuffer dump file created between upgrades, which might allow local users to obtain sensitive information from private chat conversations by reading the file.

Affected: Ubuntu:14.04:LTS: irssi, Ubuntu:16.04:LTS: irssi

It was discovered that the Irssi buf.pl script set incorrect permissions. A local attacker could use this issue to retrieve another user's window contents. (CVE-2016-7553)

Joseph Bisch discovered that Irssi incorrectly handled comparing nicks. A remote attacker could use this issue to cause Irssi to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2017-5193)

It was discovered that Irssi incorrectly handled invalid nick messages. A remote attacker could use this issue to cause Irssi to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2017-5194)

Joseph Bisch discovered that Irssi incorrectly handled certain incomplete control codes. A remote attacker could use this issue to cause Irssi to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2017-5195)

Hanno Böck and Joseph Bisch discovered that Irssi incorrectly handled certain incomplete character sequences. A remote attacker could use this issue to cause Irssi to crash, resulting in a denial of service. This issue only affected Ubuntu 16.04 LTS and Ubuntu 16.10. (CVE-2017-5196)

Hanno Böck discovered that Irssi incorrectly handled certain format strings. A remote attacker could use this issue to cause Irssi to crash, resulting in a denial of service. (CVE-2017-5356)