Malicious PDF — malware analysis report

Static analysis result for SHA-256 853d7f99698f9e5c…

MALICIOUS

PDF

75.7 KB Created: 2021-09-29 05:13:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: bb81ea50b7bb4304d177a068435f41f7 SHA-1: f5c8d7b5bcef342b9e4a8058d30f71042d44f195 SHA-256: 853d7f99698f9e5c2ba93c8cd437078fd5073d042a939c693a5ea07a7a563404
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs indicates a potential phishing or SEO manipulation attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://hensuyenpqa.traigiongthuha.com/ckfinder/userfiles/files/12694990033.pdf In PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/161477581d49f7---11039154632.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/4086420982.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/9de1e2d2f60488889e64f477375219ac/31757709528.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/17e098ac32386d630b627fb46523f905/32249364096.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/35017933358.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/bavunuvogutisizope.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/hf27abg8132ju8qar5u9ckml21/92240145186.pdfIn PDF document text
    • https://pinyardim.com/calisma2/files/uploads/91375704227.pdfIn PDF document text
    • https://amgaa.org/temp/files/21849114947.pdfIn PDF document text
    • http://qhchemicalsfeed.com/upload/files/ludufadujefidukitojomo.pdfIn PDF document text
    • http://lixupeng.com/uploads/files/7306312647.pdfIn PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/61715927101.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/91957375703.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/39868600677.pdfIn PDF document text
    • https://manhremhoangvan.com/wp-content/uploads/files/zezumemesodetoros.pdfIn PDF document text
    • https://apteka-wratislavia.pl/halatecza/userfiles/file/jeramufalavevavas.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/nugaka.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/93791949129.pdfIn PDF document text
    • https://vrrc.heart.net.tw/ckfinder/ckfiles/files/jebax.pdfIn PDF document text
    • http://balatonfurediallatorvos.hu/userfiles/file/33882708419.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614663f928020---zozekowaliwobiwex.pdfIn PDF document text
    • https://floraplant.gr/FCKeditor/userimages/file/88460146010.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=alter+your+life+emmet+fox+free+pdfPDF 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_off0000bf3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d751.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD751 10524 bytes
SHA-256: 5c98c6fc623673e47857b08394e46693428731ba75da329391c87c1235413cad
font_02_sfnt_off0000ef4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4F 18972 bytes
SHA-256: c9f06cddd8ea29f20319b2532f0f134935c0221e18eb8659ef6d376a527b92c2