Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf583c736782dc1f…

MALICIOUS

PDF

77.6 KB Created: 2021-09-16 18:26:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 999f678d8af13039ff82d1ad4b47d1c6 SHA-1: 7ddd35d06ef748cf0b1d410846db3d8968213227 SHA-256: cf583c736782dc1ff76b18540fefeee8a2a5cd1cff113475e6b538d463f5d89d
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, suggesting a link farm designed to lure users to download applications. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kythuatviet.vn/uploads/userfiles/file/juxaxozekibe.pdf In PDF document text
    • https://hrmconsulting.biz/upload/files/52506596220.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/rumagezifuvafuvazafedig.pdfIn PDF document text
    • https://zlato-invest.cz/upload/files/65268460217.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/715248052.pdfIn PDF document text
    • http://we-women.de/default/files/uploads/file/popilox.pdfIn PDF document text
    • https://mahanakhon.pacedev.com/ckupload/files/7016050833.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/suxewavotagukibudegoxade.pdfIn PDF document text
    • https://architektor.ru/uploads/file/57525907157.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bbbcbeff4---bufukawaxinozidotafub.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/45942586596.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139696b9823c---tewoniwuzamobaxewumed.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1d1c56ea9---ludisaxuboxuzelakenaja.pdfIn PDF document text
    • http://barsugo.com/ckfinder/userfiles/files/koxenuzelexivegaleposuvib.pdfIn PDF document text
    • http://lrm.mcdonalds.ua/ckfinder/userfiles/files/fasadimazilatifatugu.pdfIn PDF document text
    • http://deauville.ru/files/file/94516996797.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/xavevoxonewelefobabifage.pdfIn PDF document text
    • http://svx.su/ffile/file/2687445832.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/24279046124.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/16140c1b09d5b5---8168834568.pdfIn PDF document text
    • http://debrecen.varosom.hu/userfiles/files/zivevaxixi.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/d65db937f101a87c385d9e82325a4f19/66725160415.pdfIn PDF document text
    • https://webmenuplus.com/images/file/fakeganikewemenukunuro.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/8751625923.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=score+hero+game+apk+downloadPDF 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_off0000ca71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA71 10856 bytes
SHA-256: 56cf77baa2060e8f7f7e627e557f44d9cab4577ae5ea3cb7390e58aa0080b025
font_01_sfnt_off0000e32b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE32B 17720 bytes
SHA-256: 8f792b37f8512a402a5b395e739c3b5a58f1559a6912c5eb52ab2b964852b342
font_02_sfnt_off000110b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1