Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b3546a1d08eca4…

MALICIOUS

PDF

73.8 KB Created: 2021-06-15 22:03:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 459c0424880d6861930b629f6f97aff4 SHA-1: 4ce668e0eeb6d9a61eb724af11a3bceffa16d049 SHA-256: 77b3546a1d08eca48a245331f461fc3325938d3256c456a1978d4bca048a8fac
156 Risk Score

Malware Insights

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

This PDF document is classified as malicious, exhibiting characteristics of a phishing lure. It uses a link farm strategy, directing users to download files from compromised WordPress sites and disposable hosting, disguised as a free textbook download. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://allytemp.ru/uplcv?utm_term=introduction+to+solid+state+physics+by+wahab+pdf+free+download PDF link annotation
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/2656a591cf33377645d980b318cdf6c3/vaxaganalefojijonenetera.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607e47a04e14d---kudukobidedibaforuwoliz.pdfIn PDF document text
    • http://karunb.com/UpLoads/files/vinesalux.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/678345991a81cc3953b8bd4a959dfb96/mogalevutuv.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beb8f4a3cc5---zaruwejexosunojidoberokum.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6f5c03e821---9587916295.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/be754468e6df54e5d03e7e64a729055b/62295294829.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/95d4f88911db04843cf408f9bc6d32d0/85967521267.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/1621731541401.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160acb92cc9116---93573650847.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16090c9ae969eb---fomipafi.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4f093d51b---83855476385.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bf84c8f08b---muzatepurobojo.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/vudugoxozunumeberiwifi.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16077a9fb38015---35370012085.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/48700401172.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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_off0000d45d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD45D 5396 bytes
SHA-256: cf0ebf92d515023df90df4f417d9bb5c6418e38ced4924911c6fedb204119f4e
font_01_sfnt_off0000e6b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B6 10448 bytes
SHA-256: 2c27b97806c3eaed06d015e4187cd3a9f230539a13a44e2d2bafc0fd0bf39f86
font_02_sfnt_off00010a3d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A3D 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34