Opened 3 months ago

Closed 3 months ago

#23490 closed defect (fixed)

Fix TROVE-2017-008: Stack disclosure in hidden services logs when SafeLogging disabled

Reported by: nickm Owned by: nickm
Priority: High Milestone: Tor: 0.2.8.x-final
Component: Core Tor/Tor Version: Tor: 0.2.7.2-alpha
Severity: Normal Keywords: trove-2017-008 CVE-2017-0380
Cc: Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description (last modified by nickm)

[TROVE-2017-008.  CVE-2017-0380. Severity: medium]

Hello!

  We have found a possible problem with the code that reports an error
  during the construction of an introduction point circuit.  Because
  of this bug, it is possible that some hidden services will sometimes
  write sensitive information into their logs.

  This bug can only happen when the SafeLogging option is disabled,
  and SafeLogging is enabled by default.  If you have not disabled
  SafeLogging, then you should be fine.

  We are tracking this bug as TROVE-2017-008 and as ticket #23490. It
  is also CVE-2017-0380.


MITIGATION:

   1. If you are not running a hidden service, then you don't need
      to do anything.  This bug does not affect you.

   2. If you are running 0.2.5.x, this bug does not affect you: it
      first appeared in 0.2.7.2-alpha.  Other bugs do affect you,
      though: 0.2.5.x is pretty old!

      (If you are running 0.2.4, or 0.2.6, or 0.2.7, you should just
      upgrade. We aren't supporting those releases.)

   3. Make sure that you did not change the value of the SafeLogging
      option in your configuration -- or if you did, that you set it
      to "1".  SafeLogging needs to be turned to "0" or "relay" for
      this bug to occur.

   4. If you did disable SafeLogging, re-enable it: Set it to 1, and
      use a HUP signal to tell Tor to reload its configuration.

   5. If you did disable SafeLogging, you should delete any old logs
      that were generated with SafeLogging disabled.

      (You should be regularly removing old logs anyway, as a best
      security practice.)


ACKNOWLEDGMENTS:

    We found this when we re-added scan-build's dead assignment
    checker into the checkers that we run on Tor.  Obviously, it's
    time to make sure that scan-build gets run more frequently.

FIX:

    There are patches for this issue linked from ticket #23490 on
    our bugtracker.

    I will be putting out updated releases today.  This bug will be
    fixed in 0.2.8.15, 0.2.9.12, 0.3.0.11, 0.3.1.7, and
    0.3.2.1-alpha.

Child Tickets

Attachments (2)

trove-2017-008_for_028.patch (2.0 KB) - added by nickm 3 months ago.
trove-2017-008_for_030.patch (2.0 KB) - added by nickm 3 months ago.

Download all attachments as: .zip

Change History (7)

comment:1 Changed 3 months ago by nickm

Owner: set to nickm
Status: newaccepted

comment:2 Changed 3 months ago by nickm

Description: modified (diff)
Keywords: trove-2017-008 CVE-2017-0380 added
Summary: Fix TROVE-2017-008Fix TROVE-2017-008: Stack disclosure in hidden services logs when SafeLogging disabled
Version: Tor: 0.2.7.2-alpha

Changed 3 months ago by nickm

Changed 3 months ago by nickm

comment:3 Changed 3 months ago by nickm

Status: acceptedmerge_ready

comment:4 Changed 3 months ago by nickm

I have attached two patches here: one is the fix for 028 and 029, and the other is the fix for 030 and later.

Now, time to announce the issue and put out releases.

comment:5 Changed 3 months ago by nickm

Milestone: Tor: 0.3.1.x-finalTor: 0.2.8.x-final
Resolution: fixed
Status: merge_readyclosed

Oh hey, I forgot to close this when we put out all those releases on Monday. Closing now.

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