SB2019042708 - NULL pointer dereference in hostapd

Description

This security bulletin contains information about 1 security vulnerability.

1) NULL pointer dereference (CVE-ID: CVE-2019-11555)

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

The vulnerability exists due to a NULL pointer dereference error in hostapd (EAP server) before 2.8 and wpa_supplicant (EAP peer) before 2.8 does not validate fragmentation reassembly state properly for a case where an unexpected fragment could be received. This could result in process termination due to a NULL pointer dereference (denial of service). This affects eap_server/eap_server_pwd.c and eap_peer/eap_pwd.c. A remote attacker can perform a denial of service (DoS) attack.

Remediation

Install update from vendor's website.

References

• http://www.openwall.com/lists/oss-security/2019/04/26/1
• https://lists.debian.org/debian-lts-announce/2019/07/msg00030.html
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5T7G763UECWR7FQXOJVL67PW7C5A3SA4/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DJKZHAT5KPUN26JL77EUH563GAH5XZ5C/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IQ6P2GI5GSXRNLNIUNPARFZQVDEIGVZD/
• https://seclists.org/bugtraq/2019/May/40
• https://seclists.org/bugtraq/2019/May/64
• https://security.FreeBSD.org/advisories/FreeBSD-SA-19:03.wpa.asc
• https://security.gentoo.org/glsa/201908-25
• https://usn.ubuntu.com/3969-1/
• https://usn.ubuntu.com/3969-2/
• https://w1.fi/security/2019-5/
• https://w1.fi/security/2019-5/eap-pwd-message-reassembly-issue-with-unexpected-fragment.txt
• https://www.debian.org/security/2019/dsa-4450
• https://www.openwall.com/lists/oss-security/2019/04/18/6