CVE-2025-59391

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.

Published: 2025-12-08 Last update: 2025-12-12 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-59391 is rated Low Risk (32.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-59391

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-18 0.03% 0.06% +0.03%
2 2025-12-09 0.03%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-59391

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.9 2.5 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-59391

OS Trackers for CVE-2025-59391

vendor priority summary link
debian not yet assigned CVE-2025-59391 not yet assigned priority: Debian including 1 source packages (libcoap3), 4 status rows across 4 suites (bookworm, forky, sid, trixie): resolved 3, open 1. https://security-tracker.debian.org/tracker/CVE-2025-59391
ubuntu medium CVE-2025-59391 medium priority: Ubuntu including 3 source packages (libcoap, libcoap2, libcoap3), 17 status rows across 7 suites (bionic, focal, jammy, noble, plucky, questing, upstream): needs-triage 9, DNE 7, ignored 1. https://ubuntu.com/security/CVE-2025-59391

Affected software / configurations for CVE-2025-59391

Vendor Product Version Raw CPE
libcoap libcoap < 4.3.5a cpe:2.3:a:libcoap:libcoap:*:*:*:*:*:*:*:*

References for CVE-2025-59391

cvelogic Threat Intelligence