CVE-2026-29013
Critical · 9.8CVSS
9.8
EPSS
0.5%
Published
Apr 17, 2026
CISA due date
—
The record
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.
Affected packages
| Ecosystem | Package | Introduced | Fixed |
|---|---|---|---|
| openSUSE:Tumbleweed | libcoap | 0 | 4.3.5b-1.1 |
Related vulnerabilities
- CVE-2025-65496 NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM… Also affects libcoap
- CVE-2025-65497 NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM… Also affects libcoap
- CVE-2025-65501 Null pointer dereference in coap_dtls_info_callback() in OISM libcoap 4.3.5 allows remote… Also affects libcoap
- CVE-2025-65498 NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM… Also affects libcoap
- CVE-2025-65495 Integer signedness error in tls_verify_call_back() in src/coap_openssl.c in OISM libcoap… Also affects libcoap
- CVE-2025-65500 NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM… Also affects libcoap
- CVE-2025-65499 Array index error in tls_verify_call_back() in src/coap_openssl.c in OISM libcoap 4.3.5… Also affects libcoap
- CVE-2025-65493 NULL pointer dereference in src/coap_openssl.c in OISM libcoap 4.3.5 allows remote… Also affects libcoap