CVE-2025-34468 (GCVE-0-2025-34468)
Vulnerability from cvelistv5 – Published: 2025-12-31 18:39 – Updated: 2026-03-23 15:43
VLAI
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-121 - Stack-based Buffer Overflow
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/obgm/libcoap/pull/1737 | issue-tracking |
| https://github.com/obgm/libcoap/commit/30db3ea | patch |
| https://libcoap.net/ | product |
| https://www.vulncheck.com/advisories/libcoap-stac… | third-party-advisory |
Impacted products
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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