CVE-2026-27890
Last modified
CVE-2026-27890 is a high-severity vulnerability rated 8.2/10 on the CVSS scale. Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when processing CNCT_specific_data segments during authentication, the server assumes segments arrive in strictly ascending order. EPSS estimates a 0.46% chance of exploitation in the next 30 days.
Description
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, when processing CNCT_specific_data segments during authentication, the server assumes segments arrive in strictly ascending order. If segments arrive out of order, the Array class's grow() method computes a negative size value, causing a SIGSEGV crash. An unauthenticated attacker who knows only the server's IP and port can exploit this to crash the server. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Firebirdsql | Firebird | < 3.0.14 |
| Firebirdsql | Firebird | >= 4.0.0, < 4.0.7 |
| Firebirdsql | Firebird | >= 5.0.0, < 5.0.4 |
References
- https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-6crx-4g37-7j49Exploit, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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