CVE catalog

CVE-2025-59391

libcoap3 affected and fixed versions

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.

Severity: Medium · CVSS 6.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L
Published: Dec 8, 2025, 12:00:00 AM UTC
Source: [NVD] · [CVE record]
EPSS: 0.26% · Oct 27, 2026

Projects and upstream resources

[libcoap3][Source-reported homepage]

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Version impact has not been established. The original provider fields are retained below.

Provider details and historical evidence

Original provider fields

{
  "package_releases": [
    {
      "name": "libcoap3",
      "status": "fixed",
      "release": "sid",
      "version": "4.3.5-4"
    },
    {
      "name": "libcoap3",
      "status": "fixed",
      "release": "forky",
      "version": "4.3.5-4"
    },
    {
      "name": "libcoap3",
      "status": "fixed",
      "release": "trixie",
      "version": "4.3.4-1.1+deb13u3"
    },
    {
      "name": "libcoap3",
      "status": "vulnerable",
      "release": "bookworm",
      "version": "4.3.1-1"
    }
  ],
  "fixed_versions": [
    {
      "bug": 1122290,
      "name": "libcoap3",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": "4.3.5-2"
    },
    {
      "bug": 1122290,
      "name": "libcoap3",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": "4.3.5-2"
    },
    {
      "bug": 1122290,
      "name": "libcoap3",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": "4.3.4-1.1+deb13u2"
    },
    {
      "bug": 1122290,
      "name": "libcoap3",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": ""
    }
  ],
  "distribution_packages": [
    {
      "name": "libcoap",
      "ranges": [
        {
          "fixed": "4.3.5a",
          "introduced": "",
          "last_affected": "",
          "start_excluding": ""
        }
      ],
      "ecosystem": "cpe",
      "fixed_version": "4.3.5a",
      "provider_record_id": "NVD-CVE-2025-59391"
    }
  ]
}

[Debian bug #1122290]

Publisher notes

[bookworm] libcoap3: Minor issue

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

[libcoap3]Unknown
Details (2)
- 4.3.1-1 · amd64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
- 4.3.1-1 · arm64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
[libcoap3-bin]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.1-1 · amd64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
- 4.3.1-1 · arm64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
[libcoap3-dev]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.1-1 · amd64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
- 4.3.1-1 · arm64 · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
[libcoap3-doc]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.1-1 · all · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12
- 4.3.1-1 · all · bookworm
  Affected
  dsa · libcoap3 · debian · bookworm; dsa · libcoap3 · debian · 12

[Debian 13 (Trixie)]

[libcoap3-bin]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.4-1.1+deb13u3 · amd64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
- 4.3.4-1.1+deb13u3 · arm64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
[libcoap3-dev]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.4-1.1+deb13u3 · amd64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
- 4.3.4-1.1+deb13u3 · arm64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
[libcoap3-doc]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.4-1.1+deb13u3 · all · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
- 4.3.4-1.1+deb13u3 · all · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
[libcoap3t64]Unknown
Source package: [libcoap3]
Details (2)
- 4.3.4-1.1+deb13u3 · amd64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13
- 4.3.4-1.1+deb13u3 · arm64 · trixie
  Fixed · Fixed: 4.3.4-1.1+deb13u2
  dsa · libcoap3 · debian · 13

Observed: Oct 24, 2026, 8:20:43 AM UTC

References

[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]