Resource management error in Unbound

1) Resource management error

EUVDB-ID: #VU44440

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2011-4869

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

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

validator/val_nsec3.c in Unbound before 1.4.13p2 does not properly perform proof processing for NSEC3-signed zones, which allows remote DNS servers to cause a denial of service (daemon crash) via a malformed response that lacks expected NSEC3 records, a different vulnerability than CVE-2011-4528.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Unbound: 0.0 - 1.4.11

External links

http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071525.html
http://lists.fedoraproject.org/pipermail/package-announce/2012-January/071535.html
http://osvdb.org/77910
http://secunia.com/advisories/47326
http://unbound.nlnetlabs.nl/downloads/CVE-2011-4528.txt
http://www.debian.org/security/2011/dsa-2370
http://www.kb.cert.org/vuls/id/209659
http://exchange.xforce.ibmcloud.com/vulnerabilities/71868

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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