CVE-2020-15681
Status: ModifiedHigh (7.5)—
When multiple WASM threads had a reference to a module, and were looking up exported functions, one WASM thread could have overwritten another's entry in a shared stub table, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 82.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Base score: 7.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.09%
- Percentile among all scored CVEs: 64
- Score date: 10/9/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (1)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
Show
{
"id": "CVE-2020-15681",
"cveTags": [],
"metrics": {
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"vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "LOW",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "MEDIUM",
"obtainAllPrivilege": false,
"exploitabilityScore": 10,
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"integrityImpact": "NONE",
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"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
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"impactScore": 3.6,
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}
]
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"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
{
"vendor": "Mozilla",
"product": "Firefox",
"versions": [
{
"status": "affected",
"version": "unspecified",
"lessThan": "82",
"versionType": "custom"
}
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]
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],
"published": "2020-10-22T21:15:13.340",
"references": [
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"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1666568",
"tags": [
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],
"source": "security@mozilla.org"
},
{
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"tags": [
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"source": "security@mozilla.org"
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"tags": [
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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"tags": [
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],
"source": "af854a3a-2127-422b-91ae-364da2661108"
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],
"vulnStatus": "Modified",
"weaknesses": [
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"type": "Primary",
"source": "nvd@nist.gov",
"description": [
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"value": "NVD-CWE-noinfo"
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}
],
"descriptions": [
{
"lang": "en",
"value": "When multiple WASM threads had a reference to a module, and were looking up exported functions, one WASM thread could have overwritten another's entry in a shared stub table, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 82."
},
{
"lang": "es",
"value": "Cuando múltiples subprocesos WASM presentaban una referencia a un módulo y buscaban funciones exportadas, un subproceso WASM podría haber sobrescrito la entrada de otro en una tabla de códigos auxiliares compartida, lo que resultó en un bloqueo potencialmente explotable. Esta vulnerabilidad afecta a Firefox versiones anteriores a 82"
}
],
"lastModified": "2026-06-17T02:57:02.620",
"configurations": [
{
"nodes": [
{
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"cpeMatch": [
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"sourceIdentifier": "security@mozilla.org"
}