Date: Sat, 03 Apr 2021 08:38:53 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 254737] Missing size checks in ieee80211_ioctl_set80211() could lead to an heap overflow Message-ID: <bug-254737-227@https.bugs.freebsd.org/bugzilla/>
next in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D254737 Bug ID: 254737 Summary: Missing size checks in ieee80211_ioctl_set80211() could lead to an heap overflow Product: Base System Version: CURRENT Hardware: Any OS: Any Status: New Severity: Affects Many People Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: cutesmilee.research@protonmail.com ieee80211_ioctl_set80211() can be called with ioctl() with SIOCS80211 type = by root user (there's ieee80211_priv_check_vap_manage() which checks for PRIV_NET80211_VAP_MANAGE, and from my understading it's root only). with i_type set to IEEE80211_IOC_MLME, ieee80211_ioctl_setmlme() will be ca= lled using user provided ireq and vap structs. ireq->i_data (which is user controlled) is copied to a stack struct struct ieee80211req_mlme, and if (vap->iv_opmode is set to IEEE80211_M_IBSS or IEEE80211_M_AHDEMO and mlme.im_op is set to IEEE80211_MLME_ASSOC, setmlme_assoc_adhoc() will be called with mlme fields which are user contro= lled (mlme.im_macaddr, mlme.im_ssid_len and mlme.im_ssid). now struct ieee80211_scan_req is allocated in the heap (it's 128 bytes larg= e), and some memcpy()s are performed, the last one is the most interesting one since it copies user provided ssid, with ssid_len (which is a uint8_t so ca= n be 255 at max) to the previously allocated struct (actually to the last field, which is a 108 bytes struct), since the size can be 255, and there're no bo= unds checks (just one that checks that it isn't 0) an heap overflow up to 147 by= tes (255 - 108) can be triggered, and I think it's big enough to be exploited. at the moment I wasn=E2=80=99t able to make a poc. --=20 You are receiving this mail because: You are the assignee for the bug.=
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-254737-227>