CVE-2017-8820: Null Pointer Dereference

Published Dec 3, 2017
·
Updated

In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, remote attackers can cause a denial of service (NULL pointer dereference and application crash) against directory authorities via a malformed descriptor, aka TROVE-2017-010.

Affected Software

8 affected componentsFixes available
debian/tor
0.3.5.16-10.3.5.16-1+deb10u10.4.5.16-10.4.7.13-10.4.8.7-1
Tor Project Tor<0.2.5.16
Tor Project Tor>=0.2.6<0.2.8.17
Tor Project Tor>=0.2.9<0.2.9.14
Tor Project Tor>=0.3.0<0.3.0.13
Tor Project Tor>=0.3.1<0.3.1.9
Debian Debian Linux=8.0
Debian Debian Linux=9.0

Event History

Dec 3, 2017
CVE Published
via MITRE·07:00 AM
Data Sourced
via MITRE·07:00 AM
DescriptionWeakness
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2017-8820?

CVE-2017-8820 has a moderate severity rating as it can cause a denial of service due to a NULL pointer dereference.

2

How do I fix CVE-2017-8820?

To fix CVE-2017-8820, upgrade to Tor versions 0.2.5.16, 0.2.8.17, 0.2.9.14, 0.3.0.13, or 0.3.1.9 or later.

3

What versions of Tor are affected by CVE-2017-8820?

CVE-2017-8820 affects Tor versions before 0.2.5.16, between 0.2.6 and 0.2.8.17, between 0.2.9 and 0.2.9.14, between 0.3.0 and 0.3.0.13, and between 0.3.1 and 0.3.1.9.

4

Can CVE-2017-8820 be exploited remotely?

Yes, CVE-2017-8820 can be exploited remotely by attackers sending malformed descriptors to directory authorities.

5

Is there any workaround for CVE-2017-8820?

There are no known workarounds for CVE-2017-8820, so updating to a fixed version is the recommended approach.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203
CVE-2017-8820 - Null Pointer Dereference - SecAlerts