CVE-2026-4296
An incorrect regular expression vulnerability was identified in GitHub Enterprise Server that allowed an attacker to bypass OAuth redirect URI validation. An attacker with knowledge of a first-party OAuth application's registered callback URL could craft a malicious authorization link that, when clicked by a victim, would redirect the OAuth authorization code to an attacker-controlled domain. This could allow the attacker to gain unauthorized access to the victim's account with the scopes granted to the OAuth application. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.20.1, 3.19.5, 3.18.8, 3.17.14, 3.16.17, 3.15.21, 3.14.26. This vulnerability was reported via the GitHub Bug Bounty program.
CVSS
- Versión: 4.0
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.74%
- Percentil entre todas las CVEs puntuadas: 53
- Fecha de la puntuación: 6/10/2026
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.
- Explotación
T1203Exploitation for Client Executionexecution75 % - Impacto principal
T1078Valid Accountsstealth · persistence · privilege escalation · initial access85 % - Impacto secundario
T1556Modify Authentication Processdefense impairment · persistence · credential access70 %
UI:P (interacción del usuario requerida) + redirect OAuth malicioso → T1203. Acceso con scopes OAuth comprometidos → T1078 (valid accounts). Manipulación de validación OAuth → T1556 (modify authentication).
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
Tecnologías afectadas (1)
CWE
- CWE-185
Referencias
- https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.26
- https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.21
- https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.17
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.14
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.8
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.5
- https://docs.github.com/en/enterprise-server@3.20/admin/release-notes#3.20.1
JSON original (NVD)
Mostrar
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