Malicious PDF — malware analysis report

Static analysis result for SHA-256 8526ffc606ec4a48…

MALICIOUS

PDF

85.8 KB Created: 2021-09-18 10:44:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fbe0ab96e547d572c7d82e19fdf140e1 SHA-1: c9d9ef83e5c00eb4e0df57a0126e3f8a94af0ec9 SHA-256: 8526ffc606ec4a48a59de759e7e1b255c26aa56d2258afacda9c8f6961c461e8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or are part of a link farm designed to obscure the final destination. Heuristics indicate this is a link farm on disposable hosting and that some links point to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://ajitcoatings.com/uploads/82714528720.pdf In PDF document text
    • http://jolanyee.com/upload/files/202109102229043919.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/4hrstdascmglfkg0pf342u07il/dogijufisajuloxubaje.pdfIn PDF document text
    • http://demo-enriquemora.shopcloud.es/ckfinder/userfiles/files/tizegidekalajinolosaz.pdfIn PDF document text
    • http://lagunaapartman.hu/images/user/file/64625751930.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/kejununufebejebitu.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-15/20210915221109607142.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/33633748135.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161408f0226bdc---39131831118.pdfIn PDF document text
    • http://pneusmarene.it/images/file/32384963112.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16143d6e1cb217---3070728856.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346155ada04---temezoredul.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/45946083685.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/33271053724.pdfIn PDF document text
    • http://ablerexthailand.com/userfiles/files/38795085398.pdfIn PDF document text
    • http://formpart.com/upload/ckfinder/files/wopopivimezovuku.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/4a04b1055a4882d2c313105720f038ad/65310028248.pdfIn PDF document text
    • https://derfo.info/resimler/files/5979087711.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/lokomevatuzex.pdfIn PDF document text
    • https://quangcaowebsite.xemlaco.com/uploads/files/lukizesijug.pdfIn PDF document text
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/45516667220.pdfIn PDF document text
    • https://kultmotor.hu/images/files/97165687799.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=like+let+you+shine+apk+downloadPDF link annotation
    • https://rt9.rspo.org/ckfinder/userfiles/files/31097739963.pdfIn PDF document text
    • 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_off0000e75e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE75E 18644 bytes
SHA-256: eb08a34f0a0af0f6c85676ed777f76a4e42c1b3e21d86279199be1eb44570294
font_01_sfnt_off000118a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A7 10740 bytes
SHA-256: 05bc10058ba3c181b5c3b84979389248d0f46772fdfc860f3334c33c8bcf257d
font_02_sfnt_off00013161.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13161 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1