Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf1bc53b766ff545…

MALICIOUS

PDF

72.5 KB Created: 2021-09-17 17:09:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 984afacb5c9649837808ba7545c425f0 SHA-1: a91a1e52d68f0d483890e1a7d5cff7348a19bc63 SHA-256: bf1bc53b766ff545fca9b1f65a5a7f05a1b986e0bfaedef5e0c2231fcf7461e5
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://hk-sai.com/ckfinder/userfiles/files/9572843658.pdf In PDF document text
    • https://vetregistr.com/ckfinder/userfiles/files/90740545438.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138b0e983e66---19327097936.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/ditagexerujuxib.pdfIn PDF document text
    • http://trips-in.com/ckupload/files/99739033546.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/movukuvufowidunulinetis.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/59102569290.pdfIn PDF document text
    • http://banphimchuot.com/userfiles/file/korapotoduzutigurotuwonij.pdfIn PDF document text
    • http://a-b-i-s.net/layout/bilder/file/20406919046.pdfIn PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/bijozuxuv.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/55536108418.pdfIn PDF document text
    • http://lulanjina.net/upload/files/kefoguzodogotem.pdfIn PDF document text
    • https://camgloberealtor.com/userfiles/file/69331069677.pdfIn PDF document text
    • https://linker.tw/files/xakitedaberofeg.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///7666547537.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/42510781083.pdfIn PDF document text
    • http://tbm-mova.by/images_from_html_editor/file/16462495296.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/069f12f5fd5f0be2175a3fc8754cf4ba/22147489066.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/tinudorutujibelar.pdfIn PDF document text
    • https://xn--90ah6akb9e.xn--p1ai/f/file/zitoderutemuselevabagago.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/22481f8a30d07c97dd4fd62e1c89c28b/dufuvafuruxeferinuvi.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/613fd2580123d.pdfIn PDF document text
    • https://fengshan-zhennangong.org/upload/ckfinder/files/jusexom.pdfIn PDF document text
    • http://ldksolar-officialliquidation.com/userfiles/files/lojak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=rom+flash+apkPDF 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_off0000b9d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9D2 17372 bytes
SHA-256: abeb03755edcaf881aa7d2f05b08ee45500130df11cb2816fc0668ab28aa5cc9
font_01_sfnt_off0000e5a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5A7 10236 bytes
SHA-256: 9ac8a5d1a80c3c76c22229cbd4dbee0a8aaaa84bee39fd4d09a0bf385ec5eb10
font_02_sfnt_off0000fca9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1