#VU23961 Improper Authentication in hostapd - CVE-2019-9496

Vulnerability identifier: #VU23961

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-2019-9496

CWE-ID: CWE-287

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
hostapd
Server applications / Remote access servers, VPN

Vendor: Jouni Malinen

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to missing state validation steps when processing the SAE confirm message when in hostapd/AP mode. A remote attacker can bypass authentication process, force the hostapd process to terminate and perform a denial of service (DoS) attack on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

hostapd: 1.0 - 2.7

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External links
https://packetstormsecurity.com/files/152914/FreeBSD-Security-Advisory-FreeBSD-SA-19-03.wpa.html
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/56OBBOJJSKRTDGEXZOVFSTP4HDSDBLAE/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SVMJOFEYBGXZLFF5IOLW67SSOPKFEJP3/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TDOZGR3T7FVO5JSZWK2QPR7AOFIEJTIZ/
https://seclists.org/bugtraq/2019/May/40
https://security.FreeBSD.org/advisories/FreeBSD-SA-19:03.wpa.asc
https://w1.fi/security/2019-3/
https://www.synology.com/security/advisory/Synology_SA_19_16

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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.