CVE-2021-27913Public exploitNetwork attack vector

Account takeover via predictable session tokens

Published Aug 30, 2021 · Updated Sep 16, 2024

Weak token generation in Mautic before 3.3.4 and before 4.0.0 allows remote authenticated users to enumerate other accounts' session tokens. PointBundle's TriggerController::newAction hashes uniqid output seeded with mt_rand when creating a fallback session ID, making token entropy predictable. Low privileges and user interaction are required, and successful enumeration permits unauthorized use of another account's token.

CVSS severity3.5
Low
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Weak token generation in Mautic before 3.3.4 and before 4.0.0 allows remote authenticated users to enumerate other accounts' session tokens. PointBundle's TriggerController::newAction hashes uniqid output seeded with mt_rand when creating a fallback session ID, making token entropy predictable. Low privileges and user interaction are required, and successful enumeration permits unauthorized use of another account's token.

The record

CVE
CVE-2021-27913
Published
Aug 30, 2021
Updated
Sep 16, 2024
Vendor
Acquia
Product
Mautic
Classifications
CWE-327, CWE-338, T1528
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record 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=unspecified <3.3.4
  2. Affected versionversion=unspecified <4.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Acquia · Mauticversion=unspecified <3.3.4; version=unspecified <4.0.0

Published CVSS scores

3.5NISTAV:N/AC:M/Au:S/C:P/I:N/A:N
3.5MauticCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L
3.5NISTCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/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 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 exploitPublished

Weakness, pattern, technique

CWE-327Use of a Broken or Risky Cryptographic Algorithm
CWE-338Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
T1528Steal Application Access Token

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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