CVE-2021-38508
Status: ModifiedMedium (4.3)—
By displaying a form validity message in the correct location at the same time as a permission prompt (such as for geolocation), the validity message could have obscured the prompt, resulting in the user potentially being tricked into granting the permission. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
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: 1.64%
- Percentile among all scored CVEs: 76
- Score date: 10/7/2026
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 (4)
CWEs
- CWE-1021
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1366818
- https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html
- https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html
- https://security.gentoo.org/glsa/202202-03
- https://security.gentoo.org/glsa/202208-14
- https://www.debian.org/security/2021/dsa-5026
- https://www.debian.org/security/2022/dsa-5034
- https://www.mozilla.org/security/advisories/mfsa2021-48/
- https://www.mozilla.org/security/advisories/mfsa2021-49/
- https://www.mozilla.org/security/advisories/mfsa2021-50/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1366818
- https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html
- https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html
- https://security.gentoo.org/glsa/202202-03
- https://security.gentoo.org/glsa/202208-14
- https://www.debian.org/security/2021/dsa-5026
- https://www.debian.org/security/2022/dsa-5034
- https://www.mozilla.org/security/advisories/mfsa2021-48/
- https://www.mozilla.org/security/advisories/mfsa2021-49/
- https://www.mozilla.org/security/advisories/mfsa2021-50/
Raw JSON (NVD)
Show
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},
{
"lang": "es",
"value": "Al mostrar un mensaje de comprobación del formulario en la ubicación correcta al mismo tiempo que una solicitud de permiso (como para la geolocalización), el mensaje de comprobación podría haber ocultado la solicitud, resultando en que el usuario podría ser engañado para conceder el permiso. Esta vulnerabilidad afecta a Firefox versiones anteriores a 94, Thunderbird versiones anteriores a 91.3 y Firefox ESR versiones anteriores a 91.3"
}
],
"lastModified": "2026-06-17T04:02:15.103",
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