CVE-2026-56099

Published: Jun 18, 2026Modified: Jul 14, 2026

6.9

Vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

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CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XShow less

Source: disclosure@vulncheck.com (Secondary)

Description

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.

Affected (1)

Products: Openbsd: Openbsd

1 product

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Openbsd Openbsd	Before 2026-06-18

Related CWEs

Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

References (5)

https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd

Source: disclosure@vulncheck.com

Patch

https://pop.argus-systems.ai/advisory/adv-040.html

Source: disclosure@vulncheck.com

ExploitPatchThird Party Advisory

https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-input

Source: disclosure@vulncheck.com

Third Party Advisory

http://seclists.org/fulldisclosure/2026/Jun/17

Source: af854a3a-2127-422b-91ae-364da2661108

ExploitMailing ListPatchThird Party Advisory

http://www.openwall.com/lists/oss-security/2026/06/19/3

Source: af854a3a-2127-422b-91ae-364da2661108

ExploitMailing ListPatchThird Party Advisory

Timeline

No history available yet.