CVE-2026-25899 (GCVE-0-2026-25899)

Vulnerability from cvelistv5 – Published: 2026-02-24 21:11 – Updated: 2026-02-24 21:37
VLAI
Title
Fiber is Vulnerable to Denial of Service via Flash Cookie Unbounded Allocation
Summary
Fiber is an Express inspired web framework written in Go. In versions on the v3 branch prior to 3.1.0, the use of the `fiber_flash` cookie can force an unbounded allocation on any server. A crafted 10-character cookie value triggers an attempt to allocate up to 85GB of memory via unvalidated msgpack deserialization. No authentication is required. Every GoFiber v3 endpoint is affected regardless of whether the application uses flash messages. Version 3.1.0 fixes the issue.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-24 21:37 UTC
CWE
  • CWE-789 - Memory Allocation with Excessive Size Value
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7797 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
gofiber fiber Affected: >= 3.0.0, < 3.1.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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