Malicious PDF — malware analysis report

Static analysis result for SHA-256 71a9695bf0330598…

MALICIOUS

PDF

71.0 KB Created: 2021-10-04 09:18:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b2a6c491e89008edaac82ada6c628519 SHA-1: 919200d58475dc680d8c6182b55aa6792f5c07ed SHA-256: 71a9695bf03305988287b2c0e180eeffba3e37cf6889090bd217c0924b8d0388
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or use disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://chiuman-hk.com/images/file/litapepebamazoporuki.pdf In PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/51526443302.pdfIn PDF document text
    • http://wooshin.kr/uploaded/file/10231904736133c417568b1.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f5b6938686---50743995052.pdfIn PDF document text
    • http://tndgdemo2.com/ckfinder/userfiles/files/76406956527.pdfIn PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/surozelado.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305ce7db23c---xopevamitagivew.pdfIn PDF document text
    • https://unitedfightalliance.jordanadams.com/ckfinder/userfiles/files/85903343275.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/99755010413.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/kgifkr95reo4fjtu00jbh6id8p/95016933607.pdfIn PDF document text
    • https://mimpi1pusat.com/contents/files/67902956687.pdfIn PDF document text
    • http://old.arcnet.org.tw/ckfinder/userfiles/files/rajemorimusaki.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614ef992a4b8c---joporigomuroda.pdfIn PDF document text
    • http://elistaprezentow.pl/userfiles/file/51058663534.pdfIn PDF document text
    • http://kiszelyugyvediiroda.hu/docs/file/96727894862.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/57889717902.pdfIn PDF document text
    • http://tahyuh.com/uploads/files/202109261117295328.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/titosirufiwixugelefazubez.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/26/velomarubetegonine.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/purolubowosumamesafegur.pdfIn PDF document text
    • https://mn-lawfirm.com/box/userfiles/file/duvemonekewik.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/movofuwibuwivalawunivava.pdfIn PDF document text
    • http://designbeginnings.com/upload/file/tadonufuvuzovavazumirokuj.pdfIn PDF document text
    • https://www.vconsole.com/ckfinder/files/vuwunejalenidotizij.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=powder+actuated+tools+should+never+be+used+onPDF 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_off0000b23e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB23E 16980 bytes
SHA-256: de8c3711ca157c923615ca5919da887ddf7bf24325085eb56e39b722f74dc313
font_01_sfnt_off0000dd46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f55d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF55D 10768 bytes
SHA-256: cde6e7eb18e72f408cca0bfa2fea35b976453cff9ebdf8127cc0837f1e608e43