CVE-2025-34468 (GCVE-0-2025-34468)

Vulnerability from cvelistv5 – Published: 2025-12-31 18:39 – Updated: 2026-11-08 14:00
VLAI
Title
libcoap Stack-Based Buffer Overflow in Address Resolution DoS or Potential RCE
Summary
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).
Severity
8.2 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-02 14:18 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
libcoap libcoap Affected: 0 , ≤ 4.3.5 (semver)
Unaffected: 30db3eaa1f0464722ebea2ca2d5084aebfbd344d (git)
    cpe:2.3:a:libcoap:libcoap:*:*:*:*:*:*:*:*
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Credits
SecMate
Show details on NVD website
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