CVE-2020-6820 (GCVE-0-2020-6820)
Vulnerability from cvelistv5
Published
2020-04-24 15:56
Modified
2025-10-21 23:35
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- Use-after-free when handling a ReadableStream
Summary
Under certain conditions, when handling a ReadableStream, a race condition can cause a use-after-free. We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Thunderbird < 68.7.0, Firefox < 74.0.1, and Firefox ESR < 68.6.1.
References
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Impacted products
| Vendor | Product | Version | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ► | Mozilla | Thunderbird |
Version: unspecified < 68.7.0 |
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CISA Known exploited vulnerability
Data from the Known Exploited Vulnerabilities Catalog
Date added: 2021-11-03
Due date: 2022-05-03
Required action: Apply updates per vendor instructions.
Used in ransomware: Unknown
Notes: https://nvd.nist.gov/vuln/detail/CVE-2020-6820
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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