CVE-2026-28214

Firebird server hangs when using specific clumplet on batch creation

State: Published
Severity: 6.0 Medium
Published: Apr 17, 2026
Updated: Apr 20, 2026
Reserved: Feb 25, 2026

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 ClumpletReader::getClumpletSize() function can overflow the totalLength value when parsing a Wide type clumplet, causing an infinite loop. An authenticated user with INSERT privileges on any table can exploit this via a crafted Batch Parameter Block to cause a denial of service against the server. This issue has been fixed in versions 5.0.4, 4.0.7 and 3.0.14.

Scores

CVSS	Score	Vector	Source
4.0	6.0 Medium	CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L	GitHub_M

Weaknesses

CWE-190 Integer Overflow or Wraparound
CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

Affected Products

Product	Versions
firebirdFirebirdSQL	>= 3.0.0, < 3.0.14Affected >= 4.0.0, < 4.0.7Affected >= 5.0.0, < 5.0.4Affected

References

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