Malicious PDF — malware analysis report

Static analysis result for SHA-256 97fd2a8a556e4722…

MALICIOUS

PDF

82.4 KB Created: 2021-09-19 06:28:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a585ad2cf8e2c257db55b5a3fc505da3 SHA-1: aaf15fb16f3bf6aa15e4c655a92e74d4f9321e56 SHA-256: 97fd2a8a556e47229ebe6d06842155e4a8bc143f552d15a481adc91f18e08053
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to lure users to external sites. ClamAV detection and ML classification strongly suggest malicious intent, specifically a phishing trojan. The document body is unreadable due to encoding issues, but the heuristics and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://sukienmiennam.com/userupload/files/97261922393.pdf In PDF document text
    • http://alhambra.kopanramen.com/uploads/files/makidoganigefezeluga.pdfIn PDF document text
    • https://cantarefides.ro/admin/userfiles/file/36203002431.pdfIn PDF document text
    • http://indyskischool.com/ckfinder/userfiles/files/belima.pdfIn PDF document text
    • http://damnoen.com/ckfinder/pho/files/35767742068.pdfIn PDF document text
    • https://zhansq.cn/upload/file/xaruregat.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/kazixunuwidemanoludubom.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139a80e084b6---davoruranerabu.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/xuvutubofake.pdfIn PDF document text
    • http://bjjiffy.com/upload/31902022196.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16141a7890b4a2---35008294682.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/89520860041.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/c7712580df21873e152a7b1e63f21cbe/39546493789.pdfIn PDF document text
    • https://cafesca.info/ckfinder/userfiles/files/26758753252.pdfIn PDF document text
    • http://highdeal.linkeo.net/ckfinder/userfiles/files/zipoget.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/wezezejikurusepap.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16144bc115cda7---vozosinogipolujope.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/pujeluluw.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/notowududivomawi.pdfIn PDF document text
    • http://www.offshoreyachts.net/web_upload/editor/files/xokikitepuden.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f03c593999---fowanamadavojoputaro.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16137d0f233204---nulunikodigimopi.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/65388046229.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161350597a3b8f---gawalenugolesewagepa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=simcity+buildit+ipad+cheats+unlimited+moneyPDF 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_off0000ddda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDDA 11108 bytes
SHA-256: 53e5727f81271dbeabb0ea7fabec708be2aac2f0390eb5cac0c73a047d75181e
font_01_sfnt_off0000f75d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75D 17232 bytes
SHA-256: 15fb629fc73970eb871dbc57076e7b5593479238bc683e73d9d83161fb610eb3
font_02_sfnt_off000123da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1