Multiple vulnerabilities in Irssi

1) NULL pointer dereference

EUVDB-ID: #VU31438

Risk: Medium

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-5193

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error. A remote attacker can trigger denial of service conditions via a message without a nick.

Mitigation

Update to version 0.8.21.

Vulnerable software versions

Irssi: 0.8.0 - 0.8.20

CPE2.3

External links

https://www.openwall.com/lists/oss-security/2017/01/06/1
https://www.securityfocus.com/bid/95310
https://irssi.org/security/irssi_sa_2017_01.txt
https://lists.debian.org/debian-lts-announce/2017/12/msg00022.html
https://security.gentoo.org/glsa/201701-45

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Use-after-free

EUVDB-ID: #VU31439

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2017-5194

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing an invalid nick message. A remote attackers can cause a denial of service (crash).

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Mitigation

Update to version 0.8.21.

Vulnerable software versions

Irssi: 0.8.0 - 0.8.20

CPE2.3

External links

https://www.openwall.com/lists/oss-security/2017/01/06/1
https://www.securityfocus.com/bid/95310
https://irssi.org/security/irssi_sa_2017_01.txt
https://lists.debian.org/debian-lts-announce/2017/12/msg00022.html
https://security.gentoo.org/glsa/201701-45

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

3) Out-of-bounds read

EUVDB-ID: #VU31440

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-5195

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

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.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Irssi: 0.8.17 beta - 0.8.20

CPE2.3

External links

https://www.openwall.com/lists/oss-security/2017/01/06/1
https://www.securityfocus.com/bid/95310
https://irssi.org/security/irssi_sa_2017_01.txt
https://security.gentoo.org/glsa/201701-45

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Out-of-bounds read

EUVDB-ID: #VU31441

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-5196

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

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.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Irssi: 0.8.18 - 0.8.20

CPE2.3

External links

https://www.openwall.com/lists/oss-security/2017/01/06/1
https://www.securityfocus.com/bid/95310
https://irssi.org/security/irssi_sa_2017_01.txt
https://security.gentoo.org/glsa/201701-45

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Out-of-bounds read

EUVDB-ID: #VU31442

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-5356

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

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 (]).

Mitigation

Install update from vendor's website.

Vulnerable software versions

Irssi: 0.8.0 - 0.8.20

CPE2.3

External links

https://www.openwall.com/lists/oss-security/2017/01/12/8
https://www.openwall.com/lists/oss-security/2017/01/13/2
https://www.securityfocus.com/bid/96581
https://blog.fuzzing-project.org/55-Fuzzing-Irssi-with-Perl-Scripts.html
https://irssi.org/security/irssi_sa_2017_01.txt
https://lists.debian.org/debian-lts-announce/2017/12/msg00022.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

Risk	High
Patch available	YES
Number of vulnerabilities	5
CVE-ID	CVE-2017-5193 CVE-2017-5194 CVE-2017-5195 CVE-2017-5196 CVE-2017-5356
CWE-ID	CWE-476 CWE-416 CWE-125
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Irssi Client/Desktop applications / Messaging software
Vendor	Irssi.org