Malicious PDF — malware analysis report

Static analysis result for SHA-256 9117918a903b8c1d…

MALICIOUS

PDF

86.0 KB Created: 2021-09-15 21:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4f3f74d52b603f545160e5849c15d9b2 SHA-1: e493c877814a87a0c9c76e0a74894e419f133ff6 SHA-256: 9117918a903b8c1d56aa417b9b6d2606322b169cc39584f10d4e4b956712324e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was flagged by ClamAV as a phishing trojan and a machine learning classifier returned a high probability of maliciousness. The PDF contains numerous embedded URLs, many of which point to suspicious domains and appear to be part of a link farm, suggesting an attempt to direct users to malicious content or phishing pages. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://hiperaktivite.info/userfiles/files/43311937687.pdf In PDF document text
    • http://matrix-corporation.com/upfiles/editor/files/28131321811.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/tunizodi.pdfIn PDF document text
    • http://eros-arena.name/eros/userfiles/file/19624085108.pdfIn PDF document text
    • http://jpsacademy.com/slbdavbatala/userfiles/file/bufonuzorafinaravoginoken.pdfIn PDF document text
    • http://first-group.kr/ckupload/files/zumivunoxi.pdfIn PDF document text
    • http://turningpointdigital.com/cote_dor_import/admin/ckfinder/userfiles/files/11856714192.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134d616c9aa8---22239999975.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136ddb0c3434---36903267463.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/xifosegoratewedaf.pdfIn PDF document text
    • http://xn--tnqz8hz5cb8l.com/upload/files/72481985131.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/39975074890.pdfIn PDF document text
    • http://strandedtattoo.net/file/43905251720.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/mozobiludikuletibuv.pdfIn PDF document text
    • http://www.companyforte.com/imagenes/editor/file/91926092823.pdfIn PDF document text
    • http://theexplorerthai.com/userfiles/files/vozarexino.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/gojumoropigubedilup.pdfIn PDF document text
    • http://iccjsc.vn/images/uploads/files/91360443827.pdfIn PDF document text
    • http://taaltoetsvo.nl/userfiles/file/zujafugebe.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/koledofamogudomufo.pdfIn PDF document text
    • http://sherwoodchambergolf.org/ckfinder/userfiles/files/16297777984.pdfIn PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/2598931137.pdfIn PDF document text
    • http://uts.edu.co/portal/app/ckfinder/userfiles/files/darogalibedonakiwoxip.pdfIn PDF document text
    • http://myoffice2561.sesao33.net/UserFiles/File/gabixuranefab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=best+portrait+app+for+androidPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE05 10500 bytes
SHA-256: 1ab2701becd5e4a2fd094fc758d9c0012a9ca1d6d0f2eab4d3008b47ef45f06d
font_01_sfnt_off00010609.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10609 17180 bytes
SHA-256: 5159f4cb6b17276ca304a2a6adca181f60a6baf6ba5e8fe6f30a8566d37d86be
font_02_sfnt_off00013256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13256 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1