Malicious PDF — malware analysis report

Static analysis result for SHA-256 c66d8d1197273539…

MALICIOUS

PDF

80.2 KB Created: 2021-09-14 21:11:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 1036d4b85aed17bd938cb0c3dcba8130 SHA-1: a1bd09e475472e4e2077b24c7ef7d6cd4c4ecd67 SHA-256: c66d8d119727353916dd66238c1bc8417e729119f29bac03009bc654bc638abe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs that function as a link farm, directing users to other PDF files. Heuristics indicate these links are hosted on disposable or compromised domains, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://philabc.ru/uplcv?utm_term=botim+apk+for+pc PDF link annotation
    • http://domario.ru/userfiles/file/najutezelokujek.pdfIn PDF document text
    • https://macronew.com/upload/files/42184174791.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210914_05F95BEE8E3ABBE2.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/jizoboretifasi.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/77130556223.pdfIn PDF document text
    • http://monterroso-construpuntos.com/campannas/file/30703983531.pdfIn PDF document text
    • https://karinbentum.nl/uploads/file/80382292316.pdfIn PDF document text
    • http://huh.hu/UserFiles/File/22660082951.pdfIn PDF document text
    • http://first-group.kr/ckupload/files/siwakodulotewozaze.pdfIn PDF document text
    • https://llbyggodesign.se/UserFiles/files/38998501622.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/kbhfqkg8g0naedc7in3gbf301p/japetofedada.pdfIn PDF document text
    • http://poliinc.com/upload/files/zaxoragawovexebatebuwoba.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f94cbaf29e---sokidaxojesojikonureduzum.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16136c46b1a8d4---46704791243.pdfIn PDF document text
    • http://petgears.com/app/webroot/files/file/46092544114.pdfIn PDF document text
    • http://www.superior-inkjet.com/login/ckfinder/userfiles/files/fubonunibigodefifenad.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/85831587138.pdfIn PDF document text
    • https://segurodegranizo.ar/noticias/fckeditor/file/nibixino.pdfIn PDF document text
    • http://pb-book.com/user_file/file/naxabakiresawepuk.pdfIn PDF document text
    • http://verypool.cn/images/upload/File/86383464452.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/45049568956.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/baxabukigorareguginosira.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_off0000d4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4C1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ecd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD3 18392 bytes
SHA-256: af172543a9cec0eb14b6e3f096854bbd5a4e9888217eede23168a73658cc9fb0
font_02_sfnt_off00011d57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D57 10336 bytes
SHA-256: ccc9f8b5323aed399d04051d68aca745edf951a7fdb6426f545dd8c66cdbd5ab