VULNERABILITY INTELLIGENCE

CVE-2025-34468

CVSS score9.8 CRITICAL
EPSS probability0.75%
CISA KEVNot currently listed
Published2025-12-31
Last modified2026-09-23
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Description

libcoap versions up to and including 4.3.5, prior to commit 30db3ea, contain a stack-based buffer overflow in address resolution when attacker-controlled hostname data is copied into a fixed 256-byte stack buffer without proper bounds checking. A remote attacker can trigger a crash and potentially achieve remote code execution depending on compiler options and runtime memory protections. Exploitation requires the proxy logic to be enabled (i.e., the proxy request handling code path in an application using libcoap).

Weakness classification

  • disclosure@vulncheck.com: CWE-121
  • nvd@nist.gov: CWE-787

Primary references