Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd9f3845c6870b24…

MALICIOUS

PDF

79.8 KB Created: 2021-09-05 15:33:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d72ca6d116bc61a8c8ce5fa91325f331 SHA-1: 535063786be6f514d1be3f519146b749f2dfdba5 SHA-256: dd9f3845c6870b24959372209d61082072272a028e5e5c1603e91b42a9d8b5e7
156 Risk Score

Malware Insights

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

The PDF file contains numerous external URIs and is identified as a link farm, with many links pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The file's structure and numerous links suggest it's designed to lure users to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://medvor.ru/uplcv?utm_term=free+english+worksheets+pdf PDF link annotation
    • http://mobilesamara.com/img/files/file/tuvuxosex.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/36c45e4fc33fdd6f8a4d1b379f33a5b7/60867598674.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/21596770998.pdfIn PDF document text
    • https://h16hr15k-h19hr37urn.com/contents/files/66309253167.pdfIn PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/16940678973.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d8b12f288f---vedusoxuzugutomevok.pdfIn PDF document text
    • http://casier-a-bouteilles.fr/file/dibivuzagafa.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/81953190512.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b92e5269bde---63264480445.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c9c542759be81b61cd6c4a653c617e43/21524828488.pdfIn PDF document text
    • https://vicareyou.com/userfiles/file/darujaj.pdfIn PDF document text
    • http://zonweringbelgie.com/ckfinder/userfiles/files/8843963396.pdfIn PDF document text
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16075b69b98ff9---tawekuwuzatakametem.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/29812833846.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/e93ea811392f5b1eee142b9b31803b0c/suberepipigunafedo.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/tezirosafel.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16132a945798f4---19395933318.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a837d2f0d00---turebivubarogemigefu.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/56149960038.pdfIn PDF document text
    • http://kaies.cn/upfiles/2107281227255805721m5b5t.pdfIn PDF document text
    • http://bidhichand.org/sahodyatarntaran/userfiles/file/45153555040.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/161301cc88a7ec---kixobogolumojil.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160713662a30d0---34100595017.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/16071f1ccc0319---fenib.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/2q1ivq9jl60mbft2r6hj8lg6h7/70684698468.pdfIn PDF document text
    • http://firmykominkowe.pl/Obrazki/edytor/file/74959268646.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_off0000d42b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD42B 10772 bytes
SHA-256: 44eadb360f9e6cf497d2fcbbc72e18d225c68c7b3fd422b9d840bd2468409eb6
font_01_sfnt_off0000eca9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA9 17240 bytes
SHA-256: 0ae9be7bd3aee93bc8cb7c233a9e1e0d391a05ea59d14caa9f67541592eb4106
font_02_sfnt_off00011924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11924 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1