CVE-2026-55987

Estado: AplazadaAlta (8.1)—

OAuth2 sign-in reactivates an administrator-deactivated account on auth sources without refresh tokens (incomplete fix of #38009)

CVSS

Versión: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Puntuación base: 8.1

Probabilidad de explotación (EPSS)

Probabilidad de explotación en los próximos 30 días: 0.41%
Percentil entre todas las CVEs puntuadas: 33
Fecha de la puntuación: 4/10/2026

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).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

ExplotaciónT1210 Exploitation of Remote Serviceslateral movement85 %
Impacto principalT1078 Valid Accountsstealth · persistence · privilege escalation · initial access90 %
Impacto secundarioT1068 Exploitation for Privilege Escalationprivilege escalation75 %

AV:N/PR:L: acceso remoto con privilegios bajos (T1210). OAuth2 reactiva cuenta admin desactivada, permitiendo acceso no autorizado (T1078) y escalada de privilegios (T1068). CWE-863: autorización incompleta.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Threat Intelligence Program Privileged Account Management Application Isolation and Sandboxing Exploit Protection Update Software Application Developer Guidance

CWE

CWE-863

Referencias

JSON original (NVD)

Mostrar

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  "id": "CVE-2026-55987",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-55987",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-08-14T20:05:49.653433Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
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        "cvssData": {
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          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N",
          "integrityImpact": "HIGH",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
          "privilegesRequired": "LOW",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.2,
        "exploitabilityScore": 2.8
      }
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  },
  "affected": [
    {
      "source": "88ee5874-cf24-4952-aea0-31affedb7ff2",
      "affectedData": [
        {
          "vendor": "Gitea",
          "product": "Gitea Open Source Git Server",
          "versions": [
            {
              "status": "affected",
              "version": "0",
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              "lessThanOrEqual": "1.26.4"
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  "published": "2026-08-13T17:17:25.063",
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    {
      "url": "https://blog.gitea.com/gitea-1.27.0-is-released/",
      "source": "88ee5874-cf24-4952-aea0-31affedb7ff2"
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    {
      "url": "https://github.com/go-gitea/gitea/releases/tag/v1.27.0",
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    {
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  "vulnStatus": "Deferred",
  "weaknesses": [
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    {
      "lang": "en",
      "value": "OAuth2 sign-in reactivates an administrator-deactivated account on auth sources without refresh tokens (incomplete fix of #38009)"
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  ],
  "lastModified": "2026-08-26T16:53:48.300",
  "sourceIdentifier": "88ee5874-cf24-4952-aea0-31affedb7ff2"
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