CVE-2026-26453: Null Dereference (CVSS 7.5)

Description

ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5 contains a null pointer dereference vulnerability in the coap_server_handle_session() function when processing COAP messages containing URI_PATH options with NULL data pointers. When the server searches for a URI_PATH option matching the string "separate", it directly calls strncmp() on option_list[i].data without checking if the pointer is NULL. This causes a segmentation fault when the option's data field is NULL.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0034

Probability of exploitation

0.28%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-476 CWE-476

References

Other References

https://github.com/ipflavors/ccoap https://github.com/songxpu/bug_report/blob/master/CoAP/ccoap/VULNERABILITY_REPORT3.md https://github.com/songxpu/bug_report/blob/master/CoAP/ccoap/VULNERABILITY_REPORT3.md

Frequently Asked Questions

What is CVE-2026-26453? +

ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5 contains a null pointer dereference vulnerability in the coap_server_handle_session() function when processing COAP messages containing URI_PATH options with NULL data pointers. When the server searches for a URI_PATH option matching the string "separate", it directly calls strncmp() on option_list[i].data without checking if the pointer is NULL. This causes a segmentation fault when the option's data field is NULL. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-26453? +

CVE-2026-26453 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0034, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-26453? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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