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Vulnerability record · CVE-2025-59391 · published 8 December 2025

CVE-2025-59391: Libcoap out-of-bounds read vulnerability

Libcoap · Libcoap

A memory disclosure vulnerability exists in libcoap's OSCORE configuration parser in libcoap before release-4.3.5-patches. An out-of-bounds read may occur when parsing certain configuration values, allowing an attacker to infer or read memory beyond string boundaries in the .rodata section. This could potentially lead to information disclosure or denial of service.

6.5 CVSS 3.1 Medium EPSS 0.26% · top 84.0% CWE-125 · Out-of-bounds read
6.5CVSS 3.1 base score
0.26%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

A memory disclosure vulnerability exists in libcoap's OSCORE configuration parser in libcoap before release-4.3.5-patches. An out-of-bounds read may occur when parsing certain configuration values, allowing an attacker to infer or read memory beyond string boundaries in the .rodata section. This could potentially lead to information disclosure or denial of service.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/obgm/libcoap/pull/1730 Issue TrackingPatch
https://github.com/obgm/libcoap/releases/tag/v4.3.5a Release Notes

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2025-59391), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.