NtpBug3565 < Main

---+ NTP Bug 3565
---+++ Crafted null dereference attack from a trusted source with an authenticated mode 6 packet
   * Date Resolved: Stable (4.2.8p13) 07 Mar 2019
   * References: [[http://bugs.ntp.org/3565][Sec 3565]] / [[http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-8936][CVE-2019-8936]]
   * Affects: All ntp-4 releases up to, but not including 4.2.8p13, and 4.3.0 up to, but not including 4.3.94.  Resolved in 4.2.8p13 and 4.3.94.
   * CVSS2: MED 4.6 - [[https://nvd.nist.gov/vuln-metrics/cvss/v2-calculator?vector=(AV:N/AC:H/Au:M/C:N/I:N/A:C)][(AV:N/AC:H/Au:M/C:N/I:N/A:C)]]
   * CVSS3: MED 4.2 - [[https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H][(CVSS:3.0/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:N/A:H)]]
   * Summary: A crafted malicious authenticated mode 6 (=ntpq=) packet from a permitted network address can trigger a NULL pointer dereference, crashing =ntpd=.  Note that for this attack to work, the sending system must be on an address that the target's =ntpd= accepts mode 6 packets from, and must use a private key that is specifically listed as being used for mode 6 authorization.
   * Mitigation:
      * Use =restrict noquery= to limit addresses that can send mode 6 queries.
      * Limit access to the private =controlkey= in =ntp.keys= .
      * Upgrade to 4.2.8p13, or later, from the [[http://www.ntp.org/downloads.html][NTP Project Download Page]] or the [[http://support.ntp.org/download][NTP Public Services Project Download Page]].
   * Credit: Reported by Magnus Stubman.

   * 2019 Mar 07: Public release
   * 2019 Feb 19: Release to Advance Security Partners
   * 2019 Jan 17: Reported to Advance Notification Partners
   * 2019 Jan 15: Reported to NTF
This topic: Main > SecurityNotice > NtpBug3565
Topic revision: r1 - 2019-03-07 - 12:25:59 - HarlanStenn