CVE-2021-23960 (GCVE-0-2021-23960)
Vulnerability from cvelistv5 – Published: 2021-02-26 02:05 – Updated: 2024-08-03 19:14
VLAI
EPSS
VEX
Summary
Performing garbage collection on re-declared JavaScript variables resulted in a user-after-poison, and a potentially exploitable crash. This vulnerability affects Firefox < 85, Thunderbird < 78.7, and Firefox ESR < 78.7.
Severity
8.8 (High)
CWE
- Use-after-poison for incorrectly redeclared JavaScript variables during GC
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://www.mozilla.org/security/advisories/mfsa2… | x_refsource_MISC |
| https://www.mozilla.org/security/advisories/mfsa2… | x_refsource_MISC |
| https://www.mozilla.org/security/advisories/mfsa2… | x_refsource_MISC |
| https://bugzilla.mozilla.org/show_bug.cgi?id=1675755 | x_refsource_MISC |
Impacted products
3 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Mozilla | Firefox |
Affected:
< 85
|
guessed | |
| Mozilla | Thunderbird |
Affected:
< 78.7
|
guessed | |
| Mozilla | Firefox ESR |
Affected:
< 78.7
|
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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