CVE-2026-29013 (GCVE-0-2026-29013)

Vulnerability from cvelistv5 – Published: 2026-04-17 21:11 – Updated: 2026-04-17 21:11
VLAI?
Title
libcoap Out-of-Bounds Read in OSCORE CBOR Unwrap Handling
Summary
libcoap contains out-of-bounds read vulnerabilities in OSCORE Appendix B.2 CBOR unwrap handling where get_byte_inc() in src/oscore/oscore_cbor.c relies solely on assert() for bounds checking, which is removed in release builds compiled with NDEBUG. Attackers can send crafted CoAP requests with malformed OSCORE options or responses during OSCORE negotiation to trigger out-of-bounds reads during CBOR parsing and potentially cause heap buffer overflow writes through integer wraparound in allocation size computation.
Severity ?
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:H/SC:N/SI:N/SA:N
CWE
Assigner
References
Impacted products
Vendor Product Version
libcoap libcoap Affected: 0 , < v4.3.5b (custom)
Create a notification for this product.
Date Public ?
2026-04-17 00:00
Credits
Kazuma Matsumoto
Show details on NVD website
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}


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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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