Malicious PDF — malware analysis report

Static analysis result for SHA-256 435ac864d4bba2b9…

MALICIOUS

PDF

74.3 KB Created: 2021-06-15 21:04:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: ee7abbf379b98732e18c19b1502783fa SHA-1: dfff9b6c08f5f1fad40480afa56b0b1270b2034c SHA-256: 435ac864d4bba2b960b1eba14083d508eafbacda427347b00e290889d4be52c1
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier also strongly indicated maliciousness.

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://wastran.ru/uplcv?utm_term=muscle+gay+feet PDF link annotation
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6e00cf0c2---bupenujavewuda.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/q637emp590gavehmf5b9bssiuk/47536875915.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607c6078d5323---tikedexiguwopuzu.pdfIn PDF document text
    • http://shreyaghoshal.com/konadnew/userfiles/file/81822583764.pdfIn PDF document text
    • http://buergerforum-tirol.at/file/lutofijififot.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606c91e76fa49---68314537304.pdfIn PDF document text
    • https://khabul.mn/mmpa/userfiles/files/44406196279.pdfIn PDF document text
    • https://gangnampools.com/contents//files/wurotesumesuwiboziburu.pdfIn PDF document text
    • http://jorkurojus.com/userfiles/file/40642986154.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/3f1980a0b236bca80450873c7994ec76/80919933873.pdfIn PDF document text
    • http://biancoacolori.it/userfiles/files/15533471077.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/obt1nrd415nmp6ogs39lp8rp40/kalopifegezeju.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/78026627019.pdfIn PDF document text
    • http://www.knickmeier.net/images/pageimg/file/wupuzomosetawanogexumibo.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608074985bc4f---leratonaref.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/7b5cb9a9ecc176d459d39144e19fe57f/76420923153.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_off0000da59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA59 5060 bytes
SHA-256: 84d2496dfa93138437c0be6cab76d9b868d179661f8115aee6dde521ea36e8fc
font_01_sfnt_off0000ebbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBBD 2528 bytes
SHA-256: fa00ca2efb3740422adce526fcbaa5037a21e39b9482affa9e7d95016e3f9ad0
font_02_sfnt_off0000f6ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6ED 10920 bytes
SHA-256: 773dd9e1c654e60de3a4a453b89c648b7d4e60e3fc0c2140293308598e32935a