Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b98161f865f842…

MALICIOUS

PDF

73.5 KB Created: 2021-06-18 05:08:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 49c77a0da95d031162832b9f77b63b60 SHA-1: c656dec581b30285e633d6aedc83d897fd239dc6 SHA-256: 77b98161f865f842394264fdbad4a777f80e9165af5efd176241231612b089d6
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, many hosted on compromised WordPress sites. The embedded URL `https://crewmak.ru/uplcv?utm_term=itools+4+torrent` suggests a lure related to software downloads, potentially leading to phishing or malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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=itools+4+torrent PDF link annotation
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f496723ae6---26836197527.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/6bblfkbk9c67mfivpdi8gci510/65050476576.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9c8dc3097d---17020978107.pdfIn PDF document text
    • http://www.bash.cl/media/file/72018068790.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab60595c4ae---26741777180.pdfIn PDF document text
    • http://cnc-soustruzeni.cz/files/file/79775597657.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/4b9cfca47c3e4e39a6baed76b895340b/20544016453.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/jedukaviripawetibofon.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/c70d7e02fa356736436f16a99fead357/48901057005.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/zinulumogipizenopukutufa.pdfIn PDF document text
    • http://kiuruvedenlukio.fi/tiedostot/file/tolikigozim.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbc34d6339---60579521223.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c199db07e7d---gofajawadiwot.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/eab8b2c1f5f3712567cfd09150ca1e0c/34692037446.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608f2f7612e5c---94041492068.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d65d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD65D 4496 bytes
SHA-256: 91d52251ed896be473b59c1eb2592982fed91b19e755ff26f1a5d1f58aaab34b
font_01_sfnt_off0000e5b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B5 15948 bytes
SHA-256: dfff535d821852da0f6f2b70d73ec829011f0a801ad70e35f2319a379fe48ce7