CVE-2021-23953: Medium severity Mozilla Thunderbird vulnerability

Published Jan 26, 2021
·
Updated

If a user clicked into a specifically crafted PDF, the PDF reader could be confused into leaking cross-origin information, when said information is served as chunked data.

Affected Software

29 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<78.7
78.7
Mozilla Firefox<85.0
Mozilla Firefox ESR<78.7
Mozilla Thunderbird<78.7
Mozilla Firefox<85
85
Mozilla Firefox ESR<78.7
78.7
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 118.0.2-1
  2. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 91.12.0esr-1~deb10u1Fixed in 115.3.1esr-1~deb10u1Fixed in 102.15.0esr-1~deb11u1Fixed in 115.3.1esr-1~deb11u1Fixed in 102.15.1esr-1~deb12u1Fixed in 115.3.0esr-1~deb12u1Fixed in 115.3.0esr-1
  3. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:91.12.0-1~deb10u1Fixed in 1:115.3.1-1~deb10u1Fixed in 1:102.13.1-1~deb11u1Fixed in 1:115.3.1-1~deb11u1Fixed in 1:102.15.1-1~deb12u1Fixed in 1:115.3.1-1~deb12u1Fixed in 1:115.3.1-1
  4. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 78.7
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 85
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 78.7
  7. Upgrade

    Upgrade alpine/firefox-esr to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0
  8. Upgrade

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

    Fixed in 78.7.0-r0

Event History

Jan 26, 2021
CVE Published
12:00 AM
Feb 26, 2021
CVE Published
via MITRE·02:11 AM
Data Sourced
via MITRE·02:11 AM
DescriptionWeakness
Data Sourced
via NVD·03:15 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2021-23953?

CVE-2021-23953 has a severity rating that indicates it can lead to the leakage of sensitive cross-origin information.

2

How do I fix CVE-2021-23953?

To fix CVE-2021-23953, update Mozilla Firefox, Firefox ESR, or Thunderbird to versions later than 85, 78.7 respectively.

3

Which software is affected by CVE-2021-23953?

CVE-2021-23953 affects specific versions of Mozilla Thunderbird and Firefox, including 78.7 or earlier versions.

4

Can CVE-2021-23953 be exploited remotely?

Yes, CVE-2021-23953 can be exploited remotely if a user interacts with a specially crafted PDF.

5

What type of vulnerability is CVE-2021-23953?

CVE-2021-23953 is a cross-origin information leakage vulnerability related to the handling of chunked data in PDF files.

Company

Resources

Contact

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