CVE-2021-29969
Estado: ModificadaMedia (5.9)—
Si Thunderbird estaba configurado para usar STARTTLS para una conexión IMAP, y un atacante inyectaba las respuestas del servidor IMAP antes de la finalización del handshake STARTTLS, entonces Thunderbird no ignoraba los datos inyectados. Esto podría haber resultado en que Thunderbird mostrara información incorrecta, por ejemplo, el atacante podría haber engañado a Thunderbird para que mostrara carpetas que no existían en el servidor IMAP. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 78.12
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
- Puntuación base: 5.9
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 1.20%
- Percentil entre todas las CVEs puntuadas: 67
- Fecha de la puntuación: 8/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-552
Referencias
- https://bugzilla.mozilla.org/show_bug.cgi?id=1682370
- https://security.gentoo.org/glsa/202208-14
- https://www.mozilla.org/security/advisories/mfsa2021-30/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1682370
- https://security.gentoo.org/glsa/202208-14
- https://www.mozilla.org/security/advisories/mfsa2021-30/
JSON original (NVD)
Mostrar
{
"id": "CVE-2021-29969",
"cveTags": [],
"metrics": {
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"type": "Primary",
"source": "nvd@nist.gov",
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"version": "2.0",
"baseScore": 4.3,
"accessVector": "NETWORK",
"vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "MEDIUM",
"availabilityImpact": "NONE",
"confidentialityImpact": "PARTIAL"
},
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}
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"affected": [
{
"source": "security@mozilla.org",
"affectedData": [
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"vendor": "Mozilla",
"product": "Thunderbird",
"versions": [
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"published": "2021-08-05T20:15:08.500",
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"vulnStatus": "Modified",
"weaknesses": [
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"source": "nvd@nist.gov",
"description": [
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"descriptions": [
{
"lang": "en",
"value": "If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses prior to the completion of the STARTTLS handshake, then Thunderbird didn't ignore the injected data. This could have resulted in Thunderbird showing incorrect information, for example the attacker could have tricked Thunderbird to show folders that didn't exist on the IMAP server. This vulnerability affects Thunderbird < 78.12."
},
{
"lang": "es",
"value": "Si Thunderbird estaba configurado para usar STARTTLS para una conexión IMAP, y un atacante inyectaba las respuestas del servidor IMAP antes de la finalización del handshake STARTTLS, entonces Thunderbird no ignoraba los datos inyectados. Esto podría haber resultado en que Thunderbird mostrara información incorrecta, por ejemplo, el atacante podría haber engañado a Thunderbird para que mostrara carpetas que no existían en el servidor IMAP. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 78.12"
}
],
"lastModified": "2026-06-17T03:48:31.790",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
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}