CVE-2026-35215
Firebirdsql Firebird 3.0.0 – 3.0.14
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSummary
CVE-2026-35215 is a high-severity Divide By Zero (CWE-369) vulnerability in Firebirdsql Firebird. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 38th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-8 (Security and Privacy Engineering Principles) — 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-2026-35215 is a denial-of-service vulnerability in Firebird, an open-source relational database management system. The issue resides in the sdl_desc() function, which fails to validate the length of a decoded SDL descriptor extracted from a slice packet. This allows a zero-length descriptor to propagate, resulting in a division-by-zero error when calculating the number of slice items. Affected versions include those prior to 5.0.4, 4.0.7, and 3.0.14.
An unauthenticated remote attacker can exploit this vulnerability with low complexity by sending a specially crafted slice packet to the server, as indicated by the CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H). Successful exploitation leads to a server crash, causing a denial of service without impacting confidentiality or integrity. The root cause is tracked under CWE-369 (Divide by Zero).
Mitigation is available through patched releases: Firebird 5.0.4, 4.0.7, and 3.0.14. Security practitioners should upgrade affected installations immediately. Official advisories and release notes are published at https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-g99w-prq5-29c6 and the respective release tags: https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14, https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7, and https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-23490
Vulnerability Data
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the sdl_desc() function does not validate the length of a decoded SDL descriptor from a slice packet. A zero-length descriptor is later used to…
more
calculate the number of slice items, causing a division by zero. An unauthenticated attacker can exploit this by sending a crafted slice packet to crash the server. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation (including static/dynamic analysis) finds divide-by-zero conditions after they have been coded.
Security engineering principles can require safe-arithmetic constructs or explicit guards that keep division operands nonzero.
Validating numeric inputs before use as divisors structurally blocks zero values from reaching division operations.
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 include code analysis, input validation, and testing that prevent divide-by-zero errors.
Vulnerability identification processes can discover divide-by-zero flaws via static analysis or testing.
Routine patching and replacement can remediate divide-by-zero bugs present in deployed software.
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.
Security testing in development can detect divide-by-zero conditions before release.
Secure development lifecycle includes input validation and error-handling practices that can prevent divide-by-zero faults.
Application security requirements can mandate checks for zero denominators and safe arithmetic handling.
Secure architecture principles encourage defensive coding patterns that avoid arithmetic exceptions.
Secure coding standards directly require validation to prevent divide-by-zero and similar runtime faults.