Microsoft SharePoint Server Privilege Escalation Vulnerability

Critical Threat Advisory: This vulnerability is documented in active Ransomware campaigns. Immediate remediation required.

Technical Severity

CVSS v3.1 Metrics

CRITICAL

9.8 / 10

Minimal Risk Critical

Vector Specification

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C

Exploitation Likelihood

EPSS Prediction

94.36 %

Predictive Probability

Percentile Rank

100.0 th

Documented as more likely to be exploited than 100.0% of known CVEs.

Detection Date

Jan 10, 2024

Remediation Due

Jan 31, 2024

CISA Catalog Active

Threat Analysis

Microsoft SharePoint Server contains an unspecified vulnerability that allows an unauthenticated attacker, who has gained access to spoofed JWT authentication tokens, to use them for executing a network attack. This attack bypasses authentication, enabling the attacker to gain administrator privileges.

Remediation Directive

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

External Intelligence

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-29357

NVD

National Vulnerability Database

https://nvd.nist.gov/vuln/detail/CVE-2023-29357