#VU38065 Use-after-free in Fedora - CVE-2015-7687

Vulnerability identifier: #VU38065

Vulnerability 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-2015-7687

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Fedora
Operating systems & Components / Operating system

Vendor: Fedoraproject

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing vectors involving req_ca_vrfy_smtp and req_ca_vrfy_mta. A remote attackers can cause a denial of service (crash) or execute arbitrary code.

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

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Fedora: 22 - 23

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External links
https://lists.fedoraproject.org/pipermail/package-announce/2015-November/170448.html
https://lists.fedoraproject.org/pipermail/package-announce/2015-October/169600.html
https://www.openwall.com/lists/oss-security/2015/10/03/1
https://www.securityfocus.com/bid/76975
https://bugzilla.redhat.com/show_bug.cgi?id=1268793
https://www.opensmtpd.org/announces/release-5.7.2.txt
https://www.qualys.com/2015/10/02/opensmtpd-audit-report.txt

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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.