Integer underflow in www.gnupg libksba

1) Integer underflow

EUVDB-ID: #VU32456

Risk: Medium

CVSSv3.1: 6.4 [CVSS:3.1/CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2014-9087

CWE-ID: CWE-191 - Integer underflow

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

Integer underflow in the ksba_oid_to_str function in Libksba before 1.3.2, as used in GnuPG, allows remote attackers to cause a denial of service (crash) via a crafted OID in a (1) S/MIME message or (2) ECC based OpenPGP data, which triggers a buffer overflow.

Mitigation

Install update from vendor's website.

Vulnerable software versions

libksba: 1.3.0 - 1.3.5

External links

http://advisories.mageia.org/MGASA-2014-0498.html
http://lists.gnupg.org/pipermail/gnupg-announce/2014q4/000359.html
http://secunia.com/advisories/60073
http://secunia.com/advisories/60189
http://secunia.com/advisories/60233
http://www.debian.org/security/2014/dsa-3078
http://www.mandriva.com/security/advisories?name=MDVSA-2014:234
http://www.mandriva.com/security/advisories?name=MDVSA-2015:151
http://www.securityfocus.com/bid/71285
http://www.ubuntu.com/usn/USN-2427-1
http://blog.fuzzing-project.org/2-Buffer-overflow-and-other-minor-issues-in-GnuPG-and-libksba-TFPA-0012014.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.