Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6e4542024e82541…

MALICIOUS

PDF

73.1 KB Created: 2021-09-20 23:47:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c4ebb8783f1de1678baae2c192f05fd8 SHA-1: ec4b7eca09e83845262e72ef7b20751695ed5dc4 SHA-256: a6e4542024e8254158b17f8e93af4af36611d325b3f035a7a5caa930f9c83ef7
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are associated with compromised CMS uploads. The primary purpose appears to be directing users to potentially harmful external sites, consistent with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • 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.
  • 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://crewmak.ru/uplcv?utm_term=chrome+os+vs+android+os PDF link annotation
    • http://floramarble.com/uploads/fajarakurukobaxewanika.pdfIn PDF document text
    • https://buildingexpertsdirectory.com/ckfinder/userfiles/files/nozuxolijuv.pdfIn PDF document text
    • http://appartementslisa.it/an3_Uploads/file/fetivaxoberoba.pdfIn PDF document text
    • http://lnianemarzenie.pl/userfiles/file/bobogowoxepidizi.pdfIn PDF document text
    • https://cengilli.com/icerik_images/file/nelogomexabinix.pdfIn PDF document text
    • http://mastervin.ru/files/file/valolika.pdfIn PDF document text
    • https://www.larche-de-jules.fr/ckfinder/userfiles/files/45464610438.pdfIn PDF document text
    • https://kujainspectors.com/candyticket/uploads/page_images/files/30628629147.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/34430361812.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613274fda73f1---26630410216.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/955013130af06ba618c18aaa8b82cd30/70873583734.pdfIn PDF document text
    • http://lecostationery.com/files/file/57930091651.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/37c1bafe617f371785ade0d11f2a25fa/xurufapizikusozevabuj.pdfIn PDF document text
    • https://lrsdev.com/userfiles/file/30916756742.pdfIn PDF document text
    • http://jessie.vn/images/ckeditor/files/3896937587.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/kamoxufa.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/fetixepudimezili.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16138e6c9372d2---nediwi.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/44656524909.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/xofibefenudusutafajel.pdfIn PDF document text
    • https://barrierball.cl/ckfinder/userfiles/files/21933749873.pdfIn 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://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_off0000bbde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBDE 10468 bytes
SHA-256: 31f88cf26620c4dd6aefdd8e89ae39a3af1c3b9c429798b3a24b1786f2d4c22a
font_01_sfnt_off0000d37a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD37A 16976 bytes
SHA-256: 40cc6e7ac1eb5bfaff0e70b28779a657f303fd605a10fc44dca1c9a799b09973
font_02_sfnt_off0000ff0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF0E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1