CVE-2021-23963
Status: ModifiedMedium (4.3)—
When sharing geolocation during an active WebRTC share, Firefox could have reset the webRTC sharing state in the user interface, leading to loss of control over the currently granted permission. This vulnerability affects Firefox < 85.
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- Base score: 4.3
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 0.66%
- Percentile among all scored CVEs: 50
- 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
- CWE-281
References
Raw JSON (NVD)
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{
"id": "CVE-2021-23963",
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"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
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"published": "2021-02-26T03:15:14.137",
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"tags": [
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"weaknesses": [
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"descriptions": [
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"value": "When sharing geolocation during an active WebRTC share, Firefox could have reset the webRTC sharing state in the user interface, leading to loss of control over the currently granted permission. This vulnerability affects Firefox < 85."
},
{
"lang": "es",
"value": "Cuando se comparten la geolocalización durante un recurso compartido de WebRTC activo, Firefox podría haber restablecido el estado del intercambio de webRTC en la interfaz de usuario, conllevando a una pérdida de control sobre el permiso otorgado actualmente. Esta vulnerabilidad afecta a Firefox versiones anteriores a 85"
}
],
"lastModified": "2026-06-17T03:39:04.680",
"configurations": [
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