CVE intelligence and bounded remediation

CVE-2026-29905 — Getkirby Kirby security vulnerability

Medium CVSS 6.5

Kirby CMS through 5.1.4 allows an authenticated user with 'Editor' permissions to cause a persistent Denial of Service (DoS) via a malformed image upload. The application fails to properly validate the return value of the PHP getimagesize() function. When the system attempts to process this file for metadata or thumbnail generation, it triggers a fatal TypeError.

Severity
Medium
CVSS
6.5 (3.1)
Published
2026-03-26
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-20, CWE-252

Affected products

  • getkirby / kirby

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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