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Mallory
UnratedPublic exploit

Denial of Service in xiaozhi-esp32 MQTT Goodbye Handler

IdentifiersCVE-2026-13491CWE-20

CVE-2026-13491 is a denial-of-service vulnerability affecting xiaozhi-esp32 through version 2.2.6. The issue is in the MQTT Goodbye Handler, specifically involving the function Application::GetInstance in main/protocols/mqtt_protocol.cc. According to the provided content, manipulation of the session_id argument can trigger the flaw. The vulnerability is remotely exploitable, though attack complexity is described as high and exploitability as difficult. A public exploit is reported to exist.

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For your environment

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ANALYST BRIEF

Impact, mitigation & remediation

What it means. What to do now. Patch path, mitigations, and the assume-compromise checklist.

Impact

What an attacker gets, and what they’ve been doing with it.

Successful exploitation allows a remote attacker to cause denial of service against the affected xiaozhi-esp32 instance. Based on the available information, the primary impact is service disruption or process instability/crash triggered through crafted handling of the session_id value in MQTT goodbye processing.

Mitigation

If you can’t patch tonight, do this now.

Apply the patch identified as commit e182471f8c5a22434346bd98da34d3b66c8c8b3e. No alternative workaround or compensating control is described in the provided content.

Remediation

Patch, then assume compromise.

Upgrade xiaozhi-esp32 to a fixed version that includes patch commit e182471f8c5a22434346bd98da34d3b66c8c8b3e. If upgrading is not immediately possible, apply that specific patch to affected deployments.
PUBLIC EXPLOITS

Exploits

No public exploits tracked yet. Mallory keeps watching.

VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

ACTIVITY FEED

Recent activity

8 sources tracked across advisories and community write-ups. News coverage will land here when it surfaces.

No news coverage yet. Advisories and community discussion only.

What this page doesn’t show

The version that knows your environment.

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Exposure mapping

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Threat actor evidence

Every observed campaign linking this CVE to a named adversary.

Associated malware

Malware families riding this exploit, with evidence and IOCs.

Detection signatures

YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.

Vendor-by-vendor mapping

Cross-references every affected SKU, including bundled OEM variants.

Social activity8

Community discussion across Reddit, Mastodon, and other social sources.