Malicious PDF — malware analysis report

Static analysis result for SHA-256 621cbd98a2f94fe6…

MALICIOUS

PDF

81.9 KB Created: 2021-09-17 20:06:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3e0506c63c15674966b81f2f9dc94d82 SHA-1: 5791dd2fc2de0df197f6d3c737dfbd5595856db2 SHA-256: 621cbd98a2f94fe6e927d51724f7543de45e17b5d4e9904885c3e4c2890b196d
156 Risk Score

Malware Insights

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

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://drafthe.ru/uplcv?utm_term=ds+roms+download+free PDF link annotation
    • http://www.mariabeckmann.com/fotos/uploads/files/luromome.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143dd1b333ee---mitida.pdfIn PDF document text
    • https://maydangson.com/vietkiendo/upload/file/nijuvitezuluvukupux.pdfIn PDF document text
    • https://woodfur.in/userfiles/file/89610700072.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/b3fcd9ab2fef40fc034fffcc5b3bb4df/waxuxekabobakifi.pdfIn PDF document text
    • https://laptopserwis.com/app/webroot/media/files/jojafitudotilebagutogora.pdfIn PDF document text
    • https://zaindu.drogomedia.com/files/galeria/files/90197561018.pdfIn PDF document text
    • https://supremeroi.com/FCKeditor/file/6528003093.pdfIn PDF document text
    • https://balajitutorial.com/admin/userfiles/file/juzugofikovekomiwese.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613be6111e254---46225951930.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-9-1/20210901112905140397.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/rezekopefogine.pdfIn PDF document text
    • https://dalnoboy.com/data/filestorage/upload/files/pajoturofoxetajifoxome.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/6902454193.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/6760453990.pdfIn PDF document text
    • http://csc-021.com/userfiles/file/20210914023428_jsntad.pdfIn PDF document text
    • http://hk-bbc.com/upload/file/81622019406.pdfIn PDF document text
    • https://maggies-handmade.com/UserFiles/files/89025899137.pdfIn PDF document text
    • http://creative-format.com/upload/editor/files/rakuvej.pdfIn PDF document text
    • https://hinodecoder.com/userfiles/file/podesufa.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc40a58ca9---88559928479.pdfIn PDF document text
    • https://ckmusicdesign.nl/userfiles/file/88230401903.pdfIn PDF document text
    • https://eminentland.com/admin/userfiles/files/57313383564.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/tizidu.pdfIn PDF document text
    • http://modulobase.com/userfiles/file/56602210936.pdfIn PDF document text
    • https://easyown.ddproperty.com/datas/files/94365345308.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_off0000dada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDADA 10412 bytes
SHA-256: 2cd89a60fa3816f4567ee9eebbe8519c2b61e15e317c5c643044124e3ccc743b
font_01_sfnt_off0000f278.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF278 18216 bytes
SHA-256: abf374fe9ea7c4836d4e2ea448d784ffaa048c0bf0d4db716c5e2078038f006c
font_02_sfnt_off000121e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1