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Vulnerability record · public intelligence
CVE-2020-15678
UNKNOWN

CVE-2020-15678

Published Oct 1, 2020 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood1.88%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

When recursing through graphical layers while scrolling, an iterator may have become invalid, resulting in a potential use-after-free. This occurs because the function APZCTreeManager::ComputeClippedCompositionBounds did not follow iterator invalidation rules. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

When recursing through graphical layers while scrolling, an iterator may have become invalid, resulting in a potential use-after-free. This occurs because the function APZCTreeManager::ComputeClippedCompositionBounds did not follow iterator invalidation rules. This vulnerability affects Firefox < 81, Thunderbird < 78.3, and Firefox ESR < 78.3.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
MEDIUM
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. Security advisory ↗
  2. Security advisory ↗
  3. Security advisory ↗
  4. bugzilla.mozilla.org ↗
  5. DSA-4770 ↗
  6. [debian-lts-announce] 20201016 [SECURITY] [DLA 2408-1] thunderbird security update ↗
  7. GLSA-202010-02 ↗
  8. openSUSE-SU-2020:1780 ↗
  9. openSUSE-SU-2020:1785 ↗

Record history

Published Oct 1, 2020 · Last refreshed Nov 3, 2026

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