What’s Vulnerable › Vulnerabilities

CVE-2026-35215: Firebird: DoS via malicious slice descriptor in slice packet

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-04-17 · updated 2026-10-26
• Weakness: CWE-369

Description

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 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.

Affected products

• FirebirdSQL firebird: from 3.0.0 before 3.0.14; from 4.0.0 before 4.0.7; from 5.0.0 before 5.0.4 — fixed in 3.0.14, 4.0.7, 5.0.4

How to fix

Upgrade to a fixed version: FirebirdSQL firebird 3.0.14, 4.0.7, 5.0.4. Check the vendor advisory for mitigations.

References

• https://github.com/FirebirdSQL/firebird/releases/tag/v3.0.14
• https://github.com/FirebirdSQL/firebird/releases/tag/v4.0.7
• https://github.com/FirebirdSQL/firebird/releases/tag/v5.0.4
• https://github.com/FirebirdSQL/firebird/security/advisories/GHSA-g99w-prq5-29c6

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