Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a3e1631565e8790…

MALICIOUS

PDF

107.3 KB Created: 2021-09-03 10:35:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 81b4586773f0acddb69ecbdfa6b39361 SHA-1: a2386ae803ffc7390cd15752becefced329f12a5 SHA-256: 9a3e1631565e879082f8047ef97df0fb28a14d3e1db5ae78553cb5fbac466816
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress upload directories, suggesting it's designed to host and distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these links. No scripts were extracted, but the structure and URL findings are sufficient to infer a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://magyar-logyogyasz.hu/fileok/file/14870213756.pdf In PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1611a5970b0c96---40533536381.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/68519061721.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/jafupotox.pdfIn PDF document text
    • http://katachizu.com/img/news/files/muxonubozuwepukawabul.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/dadonotoxixesaviwexuno.pdfIn PDF document text
    • http://learnazia.com/fck/imagesfile/kepidakefero.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d34f175f963---95265924562.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/v3glcbtce5bl3u8e9bg566nauu/17676129881.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/16070888a3c78d---fivamozajopemenuv.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16100b9e43226a---veburi.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf44769773---kuwazokewan.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1612519a4ce7a8---tuxifepagipuf.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160beaf8810f15---tugutowazadexumax.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/degugenovikiwuvituse.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/13812844598.pdfIn PDF document text
    • http://aloeverajuice.cz/files/file/jupabubugoluwuxeja.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/fc9ca1120c40f291307b0db8f9ce5bb7/jorisovagigi.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b6bc004c78---92100832704.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/dinifalumasaguzonuzezus.pdfIn PDF document text
    • https://radmangroup-ye.com/rgfiles/file/gonenelikovemeneposabi.pdfIn PDF document text
    • http://thepnguyentran.vn/media/ftp/file/1132533467.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/568c9b0739a8d90793825e89ab20a544/36688041570.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/b0a9fa51dd5664e64e24b9d7aad029ad/jogirowudixezuline.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=pta+manual+therapy+continuing+educationPDF 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_off00013ce3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CE3 11008 bytes
SHA-256: df88e0ef5bed832c05ece44e5d0165631c10438ecff96123d2d1536af5dbfae8
font_01_sfnt_off00015606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15606 18860 bytes
SHA-256: 899039045c4abc155db7512e5ae337b85ad58d4e290afc6d55e74df6a343b5ae
font_02_sfnt_off000186d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x186D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1