CVE-2026-55040
Registro da vulnerabilidade com dados oficiais do NIST NVD, CISA KEV e FIRST EPSS.
Descrição
Weak authentication in Microsoft Office SharePoint allows an unauthorized attacker to bypass a security feature over a network.
- CVSS 3.x
- 9.1 CRITICAL
- Publicada
- 14/07/2026
- Atualizada
- 19/08/2026
- Status NVD
- Analyzed
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Fraqueza: CWE-1390
Exploração
- No catálogo CISA KEV
- Sim, desde 18/08/2026
- Usada por ransomware
- Não confirmado
- Prazo CISA
- 21/08/2026
- EPSS (FIRST)
- 69.5%
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Referências
Links publicados no registro oficial
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-55040
- https://github.com/sfewer-r7/CVE-2026-55040
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-55040
- https://www.rapid7.com/blog/post/ra-microsoft-sharepoint-jwt-token-authentication-bypass-cve-2026-55040/
Alguns navegadores bloqueiam sites oficiais abertos a partir da pré-visualização; copie o endereço para abrir em outra aba: https://nvd.nist.gov/vuln/detail/CVE-2026-55040