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TYPO3CMS

CVE-2009-0256

HIGH · 7.5 CVSS v2.0 Published 2009-01-22
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Session fixation vulnerability in the authentication library in TYPO3 4.0.0 through 4.0.9, 4.1.0 through 4.1.7, and 4.2.0 through 4.2.3 allows remote attackers to hijack web sessions via unspecified vectors related to (1) frontend and (2) backend authentication.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Session fixation vulnerability in TYPO3's authentication library allows remote attackers to hijack web sessions by setting or controlling the session ID before victim authentication. The vulnerability affects both frontend and backend authentication mechanisms in affected versions, enabling attackers to intercept authenticated sessions.

MitigationUpgrade to a patched TYPO3 version (4.0.10+, 4.1.8+, or 4.2.4+) that implements proper session ID regeneration upon authentication. Alternatively, implement server-side session ID regeneration on login for both frontend and backend.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
TYPO3CMS
Affected:= 4.0= 4.0.1= 4.0.2= 4.0.3= 4.0.4= 4.0.5= 4.0.6= 4.0.7= 4.0.8= 4.0.9= 4.1.0= 4.1.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:L/Au:N/C:P/I:P/A:P

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed TYPO3 version
    Locate the TYPO3 source directory and check the version file. Common locations: typo3/sysext/core/ChangeLog, typo3/ChangeLog, or access the Install Tool at /typo3/install/ and view the About/Environment section.
    Affected if The installed version is any of: 4.0, 4.0.1, 4.0.2, 4.0.3, 4.0.4, 4.0.5, 4.0.6, 4.0.7, 4.0.8, 4.0.9, 4.1.0, or 4.1.1.
  2. Confirm frontend authentication is in use
    Check if the TYPO3 installation has frontend user login enabled. Look for fe_login (Frontend User Authentication) extension loaded, or check typo3conf/localconf.php for $TYPO3_CONF_VARS['FE']['loginUser'] or similar frontend auth configuration.
    Affected if Frontend authentication (fe_users) is enabled on the site.
  3. Confirm backend authentication is in use
    Verify TYPO3 backend is accessible and functional. Check typo3/sysext/core/ for the core authentication system being used, and confirm backend admin accounts exist.
    Affected if TYPO3 backend is active and accessible.
  4. Inspect session handling configuration
    Review typo3conf/localconf.php or typo3conf/LocalConfiguration.php for session-related settings. Look for $TYPO3_CONF_VARS['FE']['session'] or $TYPO3_CONF_VARS['BE']['session'] configuration entries. Check if session ID regeneration occurs after login.
    Affected if Session configuration exists and authentication is processed, but the system does not regenerate session IDs upon successful login (session fixation is possible).

If TYPO3 version is any release from 4.0 through 4.1.1 and the frontend or backend authentication is active, the installation is vulnerable to session fixation attacks.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to a patched TYPO3 version (4.0.10+, 4.1.8+, or 4.2.4+) that implements proper session ID regeneration upon authentication. Alternatively, implement server-side session ID regeneration on login for both frontend and backend.

Fix this in TYPO3 Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2009-0256 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
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  • Version or environment caveats, and links to real fixes
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