CVE-2018-0491: Use After Free

Published Mar 5, 2018
·
Updated

A use-after-free issue was discovered in Tor 0.3.2.x before 0.3.2.10. It allows remote attackers to cause a denial of service (relay crash) because the KIST implementation allows a channel to be added more than once in the pending list.

Affected Software

18 affected componentsFixes available
torproject Tor>=0.3.2.0<0.3.2.10
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0
alpine/tor>=0.3.2.0<0.3.2.10-r0
0.3.2.10-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade alpine/tor to a version that resolves this vulnerability.

    Fixed in 0.3.2.10-r0

Event History

Mar 5, 2018
CVE Published
via MITRE·03:00 PM
Data Sourced
via MITRE·03:00 PM
DescriptionWeakness
Data Sourced
via NVD·03:29 PM
RemedyDescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·03:29 PM
DescriptionSeverityAffected Software

Frequently Asked Questions

1

What is CVE-2018-0491?

CVE-2018-0491 is a use-after-free vulnerability that was discovered in Tor 0.3.2.x before 0.3.2.10.

2

How does CVE-2018-0491 impact Tor users?

CVE-2018-0491 allows remote attackers to cause a denial of service (relay crash) in Tor.

3

What is the severity of CVE-2018-0491?

CVE-2018-0491 has a severity rating of 7.5 (High).

4

How can I fix CVE-2018-0491?

To fix CVE-2018-0491, users should update to Tor version 0.3.2.10.

5

Where can I find more information about CVE-2018-0491?

You can find more information about CVE-2018-0491 from the Tor Project's blog and ticket pages.

Company

Resources

Contact

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