CVE-2026-56099
mediumpriority · track · 21EPSS 0.005 · 43 %ileDEEURUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 2.7–6.9
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2003OpenBSD: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2026-06-18csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in OpenBSD ausnutzen, um Informationen offenzulegen.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- http://seclists.org/fulldisclosure/2026/Jun/17cnnvd
- http://www.openwall.com/lists/oss-security/2026/06/19/3cnnvd
- https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfdcnnvd
- https://pop.argus-systems.ai/advisory/adv-040.htmlcnnvd
- https://www.openbsd.org/Patchcnnvd
- https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-inputcnnvd
- https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfdenisa_euvd
- https://pop.argus-systems.ai/advisory/adv-040.htmlenisa_euvd
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