OpenBSD TKIP ieee80211_crypto_tkip.c ieee80211_michael_mic_failure comparison

Summaryinfo

A vulnerability, which was classified as critical, was found in OpenBSD. This issue affects the function ieee80211_michael_mic_failure of the file sys/net80211/ieee80211_crypto_tkip.c of the component TKIP. Executing a manipulation can lead to comparison. This vulnerability appears as CVE-2026-56101. The attack may be performed from remote. There is no available exploit. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical was found in OpenBSD (affected version not known). This vulnerability affects the function ieee80211_michael_mic_failure of the file sys/net80211/ieee80211_crypto_tkip.c of the component TKIP. The manipulation with an unknown input leads to a comparison vulnerability. The CWE definition for the vulnerability is CWE-697. The product compares two entities in a security-relevant context, but the comparison is incorrect, which may lead to resultant weaknesses. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is available at pop.argus-systems.ai. This vulnerability was named CVE-2026-56101 since 06/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 09/08/2026).

Applying the patch 1ee99dfcc4ddc87afc6395d5d3094e9d2314fb5a is able to eliminate this problem.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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Type

• Operating System

Name

• OpenBSD

License

• open-source

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CPE 2.2info

• 🔒

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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