CVE-2026-56101

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/openbsd/src/commit/1ee99dfcc4ddc87afc6395d5d3094e9d2314fb5a
https://pop.argus-systems.ai/advisory/adv-209.html
https://www.vulncheck.com/advisories/openbsd-ieee80211-crypto-tkip-c-tkip-mic-countermeasure-logic-inversion-dos

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-08 16:18

Updated : 2026-09-10 16:17

NVD link : CVE-2026-56101

Mitre link : CVE-2026-56101

CVE.ORG link : CVE-2026-56101

JSON object : View

Products Affected

No product.

CWE

CWE-697

Incorrect Comparison

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