# CVE-2026-118151: Microsoft Exchange Server external control of file name or path

Source: https://junglewise.ai/threats/cve-2026-118151-external-control-of-file-name-or-path-in-microsoft-exchange  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-10. Updated: 2026-11-10  
License: CC BY 4.0 with a link back

CVE-2026-118151 · Severity: high · CVSS 7.2 · Published 2026-11-10

Microsoft Exchange Server contains a vulnerability that allows an authenticated attacker to gain elevated privileges on a system through manipulation of file paths. An attacker with valid credentials could potentially access sensitive emails, modify mailbox data, or perform administrative actions without proper authorization.

Technologies: [Microsoft Exchange Server](https://junglewise.ai/threats/technologies/exchange-server). Vendors: [Microsoft](https://junglewise.ai/threats/vendors/microsoft).

## Quick answers

**Is CVE-2026-118151 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-118151 being exploited in the wild.

**How severe is CVE-2026-118151?** High severity, with a CVSS score of 7.2, published 10 November 2026.

**Which products and versions are affected?** Microsoft Exchange Server <UNKNOWN>.

**Is there a fix for CVE-2026-118151?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-118151 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-118151?** Check whether you run Microsoft Exchange Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a path traversal or file name control issue in Microsoft Exchange Server that allows an authenticated attacker to elevate privileges over the network. The attack requires valid credentials but does not depend on user interaction. Exploitation results in privilege escalation, allowing the attacker to perform actions beyond their current authorization level.

## Affected products

- Microsoft Exchange Server <UNKNOWN>

## Timeline

- 2026-11-10: disclosed

## References

- [https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118151](https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-118151)

## Related threats

- [Microsoft Exchange Server improper access control spoofing](https://junglewise.ai/threats/cve-2026-118208-improper-access-control-in-microsoft-exchange-server-allows-an)
- [Microsoft Exchange Server improper input validation code execution](https://junglewise.ai/threats/cve-2026-118207-improper-input-validation-in-microsoft-exchange-server-allows-an)
- [Microsoft Exchange Server weak authentication privilege elevation](https://junglewise.ai/threats/cve-2026-118157-weak-authentication-in-microsoft-exchange-server-allows-an)
- [Microsoft Exchange Server privilege elevation via untrusted security decision input](https://junglewise.ai/threats/cve-2026-118154-reliance-on-untrusted-inputs-in-a-security-decision-in-microsoft)
- [Microsoft Exchange Server algorithmic complexity denial of service](https://junglewise.ai/threats/cve-2026-118153-inefficient-algorithmic-complexity-in-microsoft-exchange-server)