CVE-2026-81826Network attack vectorHinoki check available

Account access persistence via unrevoked sessions

Published Aug 27, 2026 · Updated Aug 27, 2026

Insufficient session expiration in CIRCL Flowintel 3.3.0 and earlier allows attackers with a valid session to retain account access. The edit_user_core() and admin_edit_user_core() paths commit a new password without invalidating existing user sessions. Attackers must already possess a valid session, which retains its account permissions until natural expiration.

CVSS severity9.1
Critical
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
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Summary

What happened

Insufficient session expiration in CIRCL Flowintel 3.3.0 and earlier allows attackers with a valid session to retain account access. The edit_user_core() and admin_edit_user_core() paths commit a new password without invalidating existing user sessions. Attackers must already possess a valid session, which retains its account permissions until natural expiration.

The record

CVE
CVE-2026-81826
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
Computer Incident Response Center Luxembourg (CIRCL)
Product
Flowintel
Classifications
CWE-384, CWE-613, CAPEC-196, T1550.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 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 <=3.3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Computer Incident Response Center Luxembourg (CIRCL) · Flowintelversion=0 <=3.3.0

Published CVSS scores

9.1CIRCLCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA: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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-384Session Fixation
CWE-613Insufficient Session Expiration
CAPEC-196Session Credential Falsification through Forging
T1550.004Use Alternate Authentication Material: Web Session Cookie

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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