CVE-2026-56101

OpenBSD ieee80211_crypto_tkip.c TKIP MIC Countermeasure Logic Inversion DoS

MEDIUM
5.3
CVSS Score
Published: September 8, 2026 at 04:00 PM UTC
Updated: September 10, 2026 at 04:17 PM UTC
1 product affected across 1 vendorOpenBSD

Using OpenBSD by OpenBSD?

Get instant alerts when new vulnerabilities affect OpenBSD - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.3
Exploit prediction
EPSS 0.6%
SSVC
PoC

Description

OpenBSD before commit 1ee99df contains an inverted comparison vulnerability in the ieee80211_michael_mic_failure() function within sys/net80211/ieee80211_crypto_tkip.c that allows unauthenticated attackers within RF range to trigger denial of service by sending two malformed TKIP frames separated by more than 60 seconds. Attackers can exploit the reversed TKIP MIC failure countermeasure window check to deauthenticate all associated TKIP stations and block reassociation for up to 90 seconds, while within-window MIC failures that should engage countermeasures are silently discarded, leaving key-recovery attempts undetected.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1ee99dfcc4ddc87afc6395d5d3094e9d2314fb5a

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMVulnCheck
Attack Vector
ADJACENT_NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-697

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card