Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6d47c5923e5d3c2…

MALICIOUS

PDF

74.1 KB Created: 2021-06-23 19:07:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 443752a8e0e1e9ad77e26b941e58a283 SHA-1: c487a07a5a9436d3e0c0e64b790be9698ca5eea1 SHA-256: f6d47c5923e5d3c2038cb1f279338919a16e101b929530c56659b0fe90881c9b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit vulnerabilities or redirect users to malicious sites. The numerous external URLs, many hosted on compromised WordPress sites, suggest a link farm designed to distribute further payloads or conduct phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chcial.ru/uplcv?utm_term=dependencia+emocional+pdf PDF link annotation
    • http://yaqeen-eg.com/userfiles/file/vefoliwulusivojeko.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607228446eee7---35851931143.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1799e3fa45---kesorutavu.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/314ehd5bp5rojhef16eu0oc3a5/saremubitun.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a03a9944593---5533004024.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16088c037401ea---duzoxazeto.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607266cf892fa---mixidutusefexopugalimixif.pdfIn PDF document text
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/4fqrdrlevn392hgpoc6dv94mnf/fofikusixulezikakivax.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/1hbd3pvfgljiiqifurpjqqn0dp/bibawa.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f727cba16---58877328707.pdfIn PDF document text
    • http://skyrun-arser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210611002137307380drgvga.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bc09cc57b7b---65344965094.pdfIn PDF document text
    • https://vansuloi.com/uploads/userfiles/file/totokujusut.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/77873012921.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA9C 3080 bytes
SHA-256: 3b6c3edccbbdf68622c80e44ac099bd4bffa00507f4f1bc839f0bdbf087aa810
font_01_sfnt_off0000e5a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A6 5024 bytes
SHA-256: 0b34790245971c12fcdff7b3e3b50654eb3d3fbcb3f1980b6016d4fc9b9f04e9
font_02_sfnt_off0000f6ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BA 10900 bytes
SHA-256: 45c5b0895dc146419af2cd463a1336d699fd9f16cf6b3803f6598fa797c67c68