CVE-2026-27637Public exploitNetwork attack vector

Account takeover via predictable static authentication tokens

Published Feb 25, 2026 · Updated Feb 25, 2026

Authentication token prediction in FreeScout before 1.8.206 allows remote attackers with the APP_KEY to take over any user account. TokenAuth compares the auth_token query value to a static MD5 digest of a user ID, creation timestamp, and APP_KEY, then logs in the matching user without password validation or token expiry. Exploitation requires the APP_KEY and a guessable creation timestamp; an attacker-set in_app cookie satisfies the remaining gate and permits administrator access.

CVSS severity9.8
Critical
EPSS probability0.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication token prediction in FreeScout before 1.8.206 allows remote attackers with the APP_KEY to take over any user account. TokenAuth compares the auth_token query value to a static MD5 digest of a user ID, creation timestamp, and APP_KEY, then logs in the matching user without password validation or token expiry. Exploitation requires the APP_KEY and a guessable creation timestamp; an attacker-set in_app cookie satisfies the remaining gate and permits administrator access.

The record

CVE
CVE-2026-27637
Published
Feb 25, 2026
Updated
Feb 25, 2026
Vendor
FreeScout
Product
FreeScout
Classifications
CWE-330, T1606
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 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=< 1.8.206

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FreeScout · FreeScoutversion=< 1.8.206

Published CVSS scores

9.8GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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.

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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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-330Use of Insufficiently Random Values
T1606Forge Web Credentials

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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