CVE-2026-29013

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 out-of-bounds reads through integer wraparound in allocation size computation.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/obgm/libcoap/commit/b7847c4dbb0dbee7c90b09a673d4cae256f03718	Patch

Configurations

Configuration 1 (hide)

cpe:2.3:a:libcoap:libcoap:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-17 22:16

Updated : 2026-06-17 10:29

NVD link : CVE-2026-29013

Mitre link : CVE-2026-29013

CVE.ORG link : CVE-2026-29013

JSON object : View

Products Affected

libcoap

libcoap

CWE

CWE-125

Out-of-bounds Read

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