CVE-2022-41343
Published: 25 September 2022
Summary
CVE-2022-41343 is a high-severity Files or Directories Accessible to External Parties (CWE-552) vulnerability in Dompdf Project Dompdf. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 1.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Deeper analysis
The vulnerability is a remote file inclusion flaw in Dompdf versions prior to 2.0.1, specifically in the registerFont method of FontMetrics.php. A failure in URI validation does not stop font registration when processing a @font-face rule, allowing an attacker to supply an arbitrary URI that bypasses intended restrictions.
Unauthenticated remote attackers can exploit the issue over the network by submitting a crafted stylesheet containing a malicious @font-face directive. Successful exploitation grants read access to arbitrary files on the server, corresponding to the CVSS 7.5 rating that reflects high confidentiality impact without requiring user interaction or privileges.
The Dompdf project addressed the flaw in release 2.0.1, accompanied by a pull request that enforces proper halting of registration on URI validation failure. Related GitHub issues document the root cause and the corrective changes.
The EPSS score has reached a peak of 0.5557 with a current value of 0.5402, indicating sustained exploitation interest after disclosure.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-6724
Vulnerability details
registerFont in FontMetrics.php in Dompdf before 2.0.1 allows remote file inclusion because a URI validation failure does not halt font registration, as demonstrated by a @font-face rule.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Controls on authorized publication limit files and directories with nonpublic data from becoming accessible to external parties.
Controlling and documenting P2P file sharing prevents files and directories from being made accessible to external parties for unauthorized distribution.
Identifying and documenting file and directory locations allows restriction of access to external parties.
Protecting backup files ensures they are not accessible to external parties or unauthorized spheres.
Sanitizing equipment before off-site maintenance reduces the risk of files or directories containing sensitive data becoming accessible to external parties.
Policy restricts media access to authorized parties only, preventing exposure of resources to external or unauthorized actors.
Media access restrictions prevent files or directories from being accessible to external parties.
Employing and evaluating controls at documented alternate sites makes files and directories less likely to be accessible to external parties through physical or environmental weaknesses.