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CVE-2026-126663

Contao 4.0.0 before 5.3.54, 5.4.0 before 5.7.17, and 6.0.0 before 6.0.6 Path Traversal via Image Insert Tag

5.3 mediumFix available

Medium (5.3) in contao contao.

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Contao 4.0.0 before 5.3.54, 5.4.0 before 5.7.17, and 6.0.0 before 6.0.6 contains a path traversal vulnerability that allows content editors to read image files anywhere on the filesystem via the {{image::}} insert tag. Attackers can embed percent-encoded sequences like ..%2f that pass Validator::isInsecurePath() before rawurldecode(), making the frontend resize and serve readable image files outside the files directory.

Severity

CVSS 4.0

5.3 medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

4.3 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CWE
CWE-180 Incorrect Behavior Order: Validate Before Canonicalize
Published
Assigned by
VulnCheck (CNA)
NVD analysis
Not in the NVD yet
Record from
the CVE List, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
Contaofrom 4.0.0 before 5.3.54
Contaofrom 5.4.0-RC1 before 5.7.17
Contaofrom 6.0.0-RC1 before 6.0.6

Attack patterns (CAPEC)

  • CAPEC-3 Using Leading 'Ghost' Character Sequences to Bypass Input Filters Likelihood: Medium · Severity: Medium
  • CAPEC-71 Using Unicode Encoding to Bypass Validation Logic Likelihood: Medium · Severity: High
  • CAPEC-78 Using Escaped Slashes in Alternate Encoding Likelihood: High · Severity: High
  • CAPEC-79 Using Slashes in Alternate Encoding Likelihood: High · Severity: High
  • CAPEC-80 Using UTF-8 Encoding to Bypass Validation Logic Likelihood: High · Severity: High
  • CAPEC-267 Leverage Alternate Encoding Likelihood: High · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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