Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8ad51e1abd87d57…

MALICIOUS

PDF

67.5 KB Created: 2021-09-26 13:19:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ad891740b1f12805302128c28778ce1e SHA-1: e63c5dab13acbed0616c2e20338b929b1dcb8e2e SHA-256: b8ad51e1abd87d575293d7da012e7ba06a8e2d75818543bc9fc760537aa3823b
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised websites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://thesei.com/ In PDF document text
    • https://dawnraytech.985.tw/data/file/userfiles/files/37696893113.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b9d72c53d---43291889827.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/97267444268.pdfIn PDF document text
    • http://asja.ua/userfiles/file/burufawalazizikekuviviw.pdfIn PDF document text
    • https://ofertaromania.ro/ckfinder/userfiles/files/7647581979.pdfIn PDF document text
    • http://myapartment.de/web/editor/files/76911835088.pdfIn PDF document text
    • https://braveathlete.net/geektic/files/72175905361.pdfIn PDF document text
    • http://itineraire-consulting.com/ckfinder/userfiles/files/gawolupafaxupivojuv.pdfIn PDF document text
    • https://artemishosp-em.tw/uploads/files/202109221052547127.pdfIn PDF document text
    • http://sinojjacob.com/userfiles/file/tumovo.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/33eec3cc91398c48c1ee868c2326fb23/88745957245.pdfIn PDF document text
    • http://1-cities.com/blog_images/blog_/file/39020078945.pdfIn PDF document text
    • https://happy-playground.gr/uploads/_uploads/files/tomajagubeporazosexari.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/33720152402.pdfIn PDF document text
    • http://michael-dhom.com/webseiten/file/bepijigupafeloxenufam.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/dutebiri.pdfIn PDF document text
    • http://cdn.eagle.mn/uploads/userfiles/files/mevofegugisamofidileramo.pdfIn PDF document text
    • http://chekeeh.ir/basefile/chekeehir/files/fosobolerafalixo.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/8ba99ac07784fec5996740775fcf2b35/90080657018.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=one+piece+stampede+free+full+moviePDF 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_off0000aa13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAA13 10972 bytes
SHA-256: b63839fb8692241ae12f73e5a7afc07f8063c5e24680a2317e11fb38ecd9f40c
font_01_sfnt_off0000c397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC397 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000dba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA9 14776 bytes
SHA-256: 40849bf395f4b1985a241e8c108912c4400bdc329e11c8d731a107de8e14ed4b