Malicious PDF — malware analysis report

Static analysis result for SHA-256 a93aea7cff18bdb8…

MALICIOUS

PDF

78.2 KB Created: 2021-07-17 12:24:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: caee74dfd47969a2cca653a9fa3539e8 SHA-1: a7be7ae0a79a89e9fe076e981cd5ec2f1920ca63 SHA-256: a93aea7cff18bdb8d2b6dc0a0aaa4bc0e120e3d7477bde9f02d4aa6bb6974d6e
156 Risk Score

Malware Insights

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

This PDF file functions as a link farm, containing numerous URLs pointing to other PDF files hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to obscure the final destination and potentially track user engagement with the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://kimhoatra.com/upload/fckimagesfile/rotelebizafebizerufa.pdf In PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1e4a15c92---89474061513.pdfIn PDF document text
    • https://jdlpartnerss.com/userfiles/file/memuj.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609623c7740d9---vosasisa.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1ea5a58cb2---47729856332.pdfIn PDF document text
    • http://acevina.com/webroot/img/files/lorilujijomad.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609aac07379c0---dukazaxezogak.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16071d6587ade0---sokuwepow.pdfIn PDF document text
    • https://harrisitalia.it/uploads/file/71890633718.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/4da577b2fe2a2796fe59d0481f9e4d52/33773875160.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/ca34d7bc9e67ff20e40522b81acd655f/46340881149.pdfIn PDF document text
    • http://ajk-opakowania.eu/upload/fck/file/84757249857.pdfIn PDF document text
    • http://halaljones.com/uploads/files/momadadi.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/dthq7eo34jr3dh9g6s73k7glrf/gebib.pdfIn PDF document text
    • http://thermogroup.ru/uploads/files/tanujarefenugitativoxo.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac983b22c8d---7546452386.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a58ae8e9b---27336444843.pdfIn PDF document text
    • http://tygodnikzuzlowy.pl/ckfinder/userfiles/files/50154518089.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/98524673649.pdfIn PDF document text
    • http://stepasidemedical.com/images/uploads/file/pegobidizazuvusatulu.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/45831975297.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=maths+square+puzzles+with+answersPDF link annotation
    • 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_off0000cdc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e5d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5D7 10612 bytes
SHA-256: 1beed4b1a5bb96d4695b2827457b663d671cce963080b716514e48ff0b3623f5
font_02_sfnt_off0000fe18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE18 17408 bytes
SHA-256: 14d793065c29310282218237fdb9c73be0e19aeb78eccea5de5aa65213c79ad7