CVE-2026-79664Public exploitNetwork attack vector

Persistent authenticated access via failed token revocation

Published Aug 25, 2026 · Updated Aug 25, 2026

Insufficient session expiration in lin-snow Ech0 before 4.7.3 allows remote attackers holding a stolen never-expire token to retain access. Logout dereferences a nil ExpiresAt field, RevokeToken rejects a zero remaining lifetime, and administrative deletion removes metadata without blacklisting the JTI. Exploitation requires theft of a never-expire token, which retains its assigned scopes until the instance JWT signing secret changes.

CVSS severity9.1
Critical
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Insufficient session expiration in lin-snow Ech0 before 4.7.3 allows remote attackers holding a stolen never-expire token to retain access. Logout dereferences a nil ExpiresAt field, RevokeToken rejects a zero remaining lifetime, and administrative deletion removes metadata without blacklisting the JTI. Exploitation requires theft of a never-expire token, which retains its assigned scopes until the instance JWT signing secret changes.

The record

CVE
CVE-2026-79664
Published
Aug 25, 2026
Updated
Aug 25, 2026
Vendor
lin-snow
Product
Ech0
Classifications
CWE-755, CWE-613, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.7.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

lin-snow · Ech0version=0 <4.7.3

Published CVSS scores

9.1VulnCheck CNACVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
7.4VulnCheck CNACVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-755Improper Handling of Exceptional Conditions
CWE-613Insufficient Session Expiration
T1078Valid Accounts

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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