CVE-2026-31049
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2026-31049 is a critical-severity Improper Neutralization of Formula Elements in a CSV File (CWE-1236) vulnerability in Hostbillapp (inferred from references). Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique User Execution (T1204); ranked in the top 50% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SI-15 (Information Output Filtering) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-31049 is a critical vulnerability (CVSS 9.8, CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) affecting Hostbill versions 2025-11-24 and 2025-12-01. The issue, classified under CWE-1236, enables a remote attacker to execute arbitrary code and escalate privileges via the CSV registration field. Published on 2026-04-14, it represents a severe flaw in the application's handling of CSV imports during registration processes.
Any remote attacker with network access can exploit this vulnerability due to its low attack complexity, lack of required privileges or user interaction, and unchanged impact scope. Exploitation through the CSV registration field allows achievement of high impacts on confidentiality, integrity, and availability, culminating in arbitrary code execution and privilege escalation on the affected Hostbill instance.
Vendor-provided resources detail potential mitigations, including a security advisory at https://blog.hostbillapp.com/2025/12/03/hostbill-security-advisory/, changelog at https://hostbillapp.com/changelog, and release notes for versions 11-27-2025 and 12-01-2025 at https://hostbillapp.com/release-notes/11-27-2025.html and https://hostbillapp.com/release-notes/12-01-2025.html. A GitHub repository at https://github.com/Muhammad5235/HostBill-CVEs-2025/blob/main/Missing%20Server-Side%20Validation/Registration%20fields%20%26%20Import%20Csv documents the missing server-side validation underlying the flaw.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-22253
Vulnerability Data
An issue in Hostbill v.2025-11-24 and 2025-12-01 allows a remote attacker to execute arbitrary code and escalate privileges via the CSV registration field
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.2.10
Mitigating Controls (NIST 800-53 r5) AI
Output filtering/validation directly stops unneutralized formula elements from being written into CSV files.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly require output neutralization for untrusted CSV content to block formula injection.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Secure SDLC mandates input validation and output encoding that directly prevents formula injection in CSV exports.
Application security requirements include rules for safe CSV generation and handling of untrusted data.
Secure architecture principles encourage safe data export design but do not specifically address CSV formula neutralization.
Secure coding standards explicitly require neutralization of special characters when writing CSV files.
Security testing in development can detect formula injection but does not itself implement the mitigation.