CVE-2021-23994: High severity thunderbird vulnerability

Published Apr 19, 2021
·
Updated

A WebGL framebuffer was not initialized early enough, resulting in memory corruption and an out of bound write.

Affected Software

9 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<78.10
78.10
Mozilla Firefox<88.0
Mozilla Firefox ESR<78.10
Mozilla Thunderbird<78.10
Mozilla Firefox<88
88
Mozilla Firefox ESR<78.10
78.10

Event History

Apr 19, 2021
CVE Published
via Mozilla·12:00 AM
Jun 24, 2021
CVE Published
via MITRE·01:26 PM
Data Sourced
via MITRE·01:26 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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-2021-23994?

CVE-2021-23994 has a medium severity level due to the potential for memory corruption and out-of-bounds write issues.

2

How do I fix CVE-2021-23994?

To fix CVE-2021-23994, update Mozilla Thunderbird and Firefox ESR to version 78.10 or later.

3

What software is affected by CVE-2021-23994?

CVE-2021-23994 affects Mozilla Thunderbird versions earlier than 78.10 and Firefox ESR versions earlier than 78.10.

4

Can CVE-2021-23994 lead to exploitation?

Yes, CVE-2021-23994 can potentially lead to exploitation through memory corruption vulnerabilities.

5

Is there a specific version of Firefox that resolves CVE-2021-23994?

Yes, upgrading to Firefox version 88 or later will resolve CVE-2021-23994.

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