CVE-2026-35215: Firebird: DoS via malicious slice descriptor in slice packet
Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and 3.0.14, the sdldesc() 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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Firebirdto a version that resolves this vulnerability.Fixed in 5.0.4 - Upgrade
Upgrade
Firebirdto a version that resolves this vulnerability.Fixed in 4.0.7 - Upgrade
Upgrade
Firebirdto a version that resolves this vulnerability.Fixed in 3.0.14
Event History
Frequently Asked Questions
What is the severity of CVE-2026-35215?
CVE-2026-35215 is classified as a denial-of-service (DoS) vulnerability affecting Firebird database versions prior to 5.0.4, 4.0.7, and 3.0.14.
How do I fix CVE-2026-35215?
To remediate CVE-2026-35215, update your Firebird database to version 5.0.4 or later, or to version 4.0.7 or 3.0.14.
Which versions of Firebird are affected by CVE-2026-35215?
CVE-2026-35215 affects Firebird versions prior to 5.0.4, 4.0.7, and 3.0.14.
What is the main cause of CVE-2026-35215?
The vulnerability arises from the sdl_desc() function not validating the length of a decoded SDL descriptor from a slice packet.
Can CVE-2026-35215 lead to data loss?
While CVE-2026-35215 is a denial-of-service vulnerability, it does not directly cause data loss but can disrupt database availability.