How severe is CVE-2025-53771?

CVE-2025-53771 has a CVSS score of 6.5/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2025-53771?

Affected package information for CVE-2025-53771 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2025-53771?

No fixed version has been published for CVE-2025-53771 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2025-53771 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-53771 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-53771?

CVE-2025-53771 has an EPSS (Exploit Prediction Scoring System) score of 99.9%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

What type of vulnerability is CVE-2025-53771?

CVE-2025-53771 is classified as Improper Authentication (CWE-287). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Which products and versions are affected by CVE-2025-53771?

CVE-2025-53771 affects microsoft sharepoint server (2 versions, e.g. 2016, 2019). Check the affected-products list on this page against your deployed version to confirm exposure.

Is there exploit tooling available for CVE-2025-53771?

A Nuclei detection template exists for CVE-2025-53771, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2025-53771 published, and has it been updated?

CVE-2025-53771 was published on July 20, 2025 and was last updated on August 14, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CVE-2025-53771

MEDIUM

Improper authentication in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.

Published

Jul 20, 2025

Updated

Aug 14, 2025

Affected

0 pkgs

Patched

None yet

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

99.9%probability of exploitation in next 30 days

Very High Risk100th percentile+67.73%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

Improper authentication in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.

Affected Products

1 product · 3 configurations

Application

sharepoint servermicrosoft

< 16.0.18526.20508

2 versions

20162019

Frequently Asked Questions

Improper authentication in Microsoft Office SharePoint allows an unauthorized attacker to perform spoofing over a network.

O3 Security · Impact-Aware SCA

Is CVE-2025-53771 in your stack?

O3 detects CVE-2025-53771 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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