#VU33599 NULL pointer dereference in Fedora - CVE-2016-6866

Vulnerability identifier: #VU33599

Vulnerability 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-2016-6866

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Fedora
Operating systems & Components / Operating system

Vendor: Fedoraproject

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 vectors involving an invalid password hash, which triggers a NULL pointer dereference and crash.

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

Vulnerable software versions

Fedora: 24 - 25

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External links
https://git.suckless.org/slock/commit/?id=d8bec0f6fdc8a246d78cb488a0068954b46fcb29
https://s1m0n.dft-labs.eu/files/slock/slock.txt
https://www.openwall.com/lists/oss-security/2016/08/18/22
https://www.openwall.com/lists/oss-security/2016/08/18/24
https://www.securityfocus.com/bid/92546
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2FYPV6QQPPYBL3Z2BYNYEJB67FSC55OR/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RZPEJQNVODYSI4WQXM5GQKXRO7TPK2VG/

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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.