HTTP response splitting via certificate hostname mismatch
Published Jul 22, 2025 · Updated Jul 29, 2026
Certificate hostname validation in HotelRunner B2B before 04.06.2025 allows remote authenticated users to split HTTP responses. The CNA identifies acceptance of a certificate whose host does not match, but it does not disclose the endpoint or code path that places attacker-controlled data in a response. Exploitation requires low-privileged access and user interaction; the split response can expose or alter limited data without interrupting service.
Summary
What happened
Certificate hostname validation in HotelRunner B2B before 04.06.2025 allows remote authenticated users to split HTTP responses. The CNA identifies acceptance of a certificate whose host does not match, but it does not disclose the endpoint or code path that places attacker-controlled data in a response. Exploitation requires low-privileged access and user interaction; the split response can expose or alter limited data without interrupting service.
The record
- CVE
- CVE-2025-4295
- Published
- Jul 22, 2025
- Updated
- Jul 29, 2026
- Vendor
- HotelRunner
- Product
- HotelRunner B2B Network
- Classifications
- CWE-297, CAPEC-34, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 22, 2025CVE publishedPublication date reported by the CVE source.
- Jul 29, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <04.06.2025
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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