ReviewHigh

CVE-2020-15670

Mozilla Firefox, Firefox ESR, Thunderbird

Mozilla developers reported memory safety bugs present in Firefox for Android 79. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 80, Firefox ESR < 78.2, Thunderbird < 78.2, and Firefox for Android < 80.

CVSS
8.8
EPSS
1.06%
62.3% percentile
CISA KEV
Not listed
Published
2020.10.02
PRIORITY ASSESSMENT

Review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability1.06%
Technical severityCVSS 8.8

Vulnerability overview

Mozilla developers reported memory safety bugs present in Firefox for Android 79. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 80, Firefox ESR < 78.2, Thunderbird < 78.2, and Firefox for Android < 80.

Affected product and versions

Product
Mozilla Firefox, Firefox ESR, Thunderbird
Affected versions
>= unspecified < 80, >= unspecified < 78.2, < 80.0
Fixed versions
80.0, 78.2

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Mozilla Firefox, Firefox ESR, Thunderbird and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CWE
CWE-362, CWE-416, CWE-617