CVE-2026-56099

OpenBSD before commit 6a23123 (2026-06-18) contains an out-of-bounds read vulnerability in the mpls_do_error function within sys/netmpls/mpls_input.c that allows remote attackers to disclose kernel stack memory by sending crafted MPLS frames with 16 labels and no Bottom-of-Stack bit set.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd	Patch
https://pop.argus-systems.ai/advisory/adv-040.html	Exploit Patch Third Party Advisory
https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-input	Third Party Advisory
http://seclists.org/fulldisclosure/2026/Jun/17	Exploit Mailing List Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2026/06/19/3	Exploit Mailing List Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:o:openbsd:openbsd:*:*:*:*:*:*:*:*

History

26 Oct 2026, 11:10

Type	Values Removed	Values Added
Summary		(es) OpenBSD antes del commit 6a23123 (18-06-2026) contiene una vulnerabilidad de lectura fuera de límites en la función mpls_do_error dentro de sys/netmpls/mpls_input.c que permite a atacantes remotos divulgar memoria de la pila del kernel mediante el envío de tramas MPLS manipuladas con 16 etiquetas y sin el bit Bottom-of-Stack establecido.

Information

Published : 2026-06-18 20:16

Updated : 2026-10-26 11:10

NVD link : CVE-2026-56099

Mitre link : CVE-2026-56099

CVE.ORG link : CVE-2026-56099

JSON object : View

Products Affected

openbsd

openbsd

CWE

CWE-125

Out-of-bounds Read

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