CVE-2026-56099OpenBSD mpls_do_error Kernel Stack Memory Disclosure via MPLS Input
Updated under an hour ago ()
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It affects openbsd src and 1 other product. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
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Free account, 1 product
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
- 5.3 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- Weakness (CWE)
- CWE-125
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- VulnCheck
- NVD analysis
- Analyzed
- Record last updated
- Jul 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
openbsd src openbsd:src (from the name) | before 6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd | CNA record |
openbsd openbsd openbsd:openbsd | before 2026-06-18 | NVD |
References
- https://pop.argus-systems.ai/advisory/adv-040.htmltechnical-description, exploit, patch, third-party-advisory
- https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfdpatch
- https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-inputthird-party-advisory
- http://seclists.org/fulldisclosure/2026/Jun/17exploit, mailing-list, patch, third-party-advisory
- http://www.openwall.com/lists/oss-security/2026/06/19/3exploit, mailing-list, patch, third-party-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.