Malicious PDF — malware analysis report

Static analysis result for SHA-256 d21b94fa555b523a…

MALICIOUS

PDF

68.9 KB Created: 2021-09-17 00:50:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0594027868940c6a158a2229b77fe333 SHA-1: 50eb78700baa827c7de5ec7f02e507a322dc0ef9 SHA-256: d21b94fa555b523a49959f51802f2165ac60b6617ac9c9ef13fe548edb180880
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm heuristics, indicating its primary purpose is to redirect users to external sites. Several URLs point to WordPress installations, suggesting compromised sites are being used to host or distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://archism.ru/uplcv?utm_term=keypad+settings+android PDF link annotation
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8649016cf---80720738474.pdfIn PDF document text
    • http://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/41008397511.pdfIn PDF document text
    • https://www.pollackmihalyiskola.hu/ckfinder/userfiles/files/vutisonewexa.pdfIn PDF document text
    • https://protraderin.com/userfiles/file/tisifufeken.pdfIn PDF document text
    • http://fruitsad.pl/images/file/85479611191.pdfIn PDF document text
    • http://avvocatogiuliani.it/userfiles/files/17487613317.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/rkrgs4uvq2uuj41hogoon7h2bi/vupunepanubi.pdfIn PDF document text
    • https://journalofcritique.com/ckdosyalari/upload/files/zifodupozomitebiwo.pdfIn PDF document text
    • http://woykoff.hu/upload/file/tajozaxefajuxobewavinupa.pdfIn PDF document text
    • https://matrixx.lu/images/fupegoguwederipereserilup.pdfIn PDF document text
    • https://doctmcooper.com/userfiles/files/lesajogejidakasepesare.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/47576823354.pdfIn PDF document text
    • http://hotechike.com/files/files/kinubirot.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/vb6on4223h4j94rts3lks632nr/78775625638.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/78306988100.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/29688485937.pdfIn PDF document text
    • https://losungversorger.com/product/file/sowugotabi.pdfIn PDF document text
    • https://brothers-music.com/ckfinder/userfiles/files/dunez.pdfIn PDF document text
    • https://eliteplacementagency.com/uploads/files/70910942003.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/fuwijopi.pdfIn PDF document text
    • http://jmyhship.com/uploadfile/files/84561389527.pdfIn PDF document text
    • http://lnshiyue.com/userfiles/file/20210908132544_1659025816.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/nuvuxejizi.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_off0000b225.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB225 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA37 14256 bytes
SHA-256: c3471ba1587c489affec5ffe06b560e2d40decd5c7cc4deca705468da806485f
font_02_sfnt_off0000ede5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE5 10624 bytes
SHA-256: 9c3e9ec2462783ce4f832c60f588fd777a854a2da603cb641dc351e140163829