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Multiple vulnerabilities released in NTP

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Re: Multiple vulnerabilities released in NTP

#12

Post by skuhn »

hiphopyo wrote: post #3

Might want to check out OpenBSD's OpenNTPD: http://www.openntpd.org/

The portable version (for Linux and other OSes) is unmaintained and the last release is from 2006. I don't use it on that basis alone.

Also, the last release of non-portable openntpd is from 2009.

Re: Multiple vulnerabilities released in NTP

#13

Post by yrro »

voidz wrote: post #7

The ntpd daemon does not run as root. So, how is it able to change the time of the system? Does it use setuid, or caps, or something else? I wonder because this would also affect what arbitrary code could be run as the ntp user.

It appears to use capabilities:

  $ ps u 561
  USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
  ntp        561  0.0  0.0   5856   780 ?        Ss   Jul14  22:37 /usr/sbin/ntpd -p /var/run/ntpd.pid -g -u 103:107

  $ /sbin/getpcaps 561
  Capabilities for `561': = cap_net_bind_service,cap_sys_time+ep

Re: Multiple vulnerabilities released in NTP

#15

Post by feld »

hiphopyo wrote: post #3

Might want to check out OpenBSD's OpenNTPD: http://www.openntpd.org/

I've talked to several developers about the state of NTP daemons and neither OpenNTPD nor DragonflyBSD's dntpd are suitable replacements. Neither of those support NTP Authentication nor do they have all of the required algorithms required for proper timekeeping.

Re: Multiple vulnerabilities released in NTP

#17

Post by arca_vorago »

This is interesting timing, I was just in the freenode #linux channel yesterday asking about security issues with NTP. I got told it was a non-issue and that I was "tilting at windmills". I have been using chronyd in Alpine linux to good effect so far, but have really been wondering how bad it would be if I just turned it all off.

Re: Multiple vulnerabilities released in NTP

#18

Post by ck2 »

A remote attacker can send a carefully crafted packet that can overflow a stack buffer and potentially allow malicious code to be executed with the privilege level of the ntpd process.

Geez, in a time sync program? Nothing is safe anymore.

Re: Multiple vulnerabilities released in NTP

#19

Post by tedunangst »

ck2 wrote: post #18

A remote attacker can send a carefully crafted packet that can overflow a stack buffer and potentially allow malicious code to be executed with the privilege level of the ntpd process. Geez, in a time sync program? Nothing is safe anymore.

ntpd is a, uh, rather large time sync program.

Re: Multiple vulnerabilities released in NTP

#20

Post by kbar13 »

arca_vorago wrote: post #17

This is interesting timing, I was just in the freenode #linux channel yesterday asking about security issues with NTP. I got told it was a non-issue and that I was "tilting at windmills". I have been using chronyd in Alpine linux to good effect so far, but have really been wondering how bad it would be if I just turned it all off.

having a host clock that is out of sync can be incredibly troublesome, especially if you have more than one system.
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