Malicious PDF — malware analysis report

Static analysis result for SHA-256 2651940d938b5522…

MALICIOUS

PDF

84.6 KB Created: 2021-09-06 19:21:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 8282b67c685455685043d534f612f142 SHA-1: afc352f63925c4d23de495aa416a49f627bf68f2 SHA-256: 2651940d938b5522ca72c2eb38058084e19c06ddfa2828b517a38e8adefd196b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV specifically identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, suggest a link farm designed to redirect users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicates a deliberate effort to obscure the true destination and leverage compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/9qhsvo1mg9rctair0c6aq064e4/80261873200.pdf In PDF document text
    • http://jjkxmy.com/upload/files/202108090225542973.pdfIn PDF document text
    • https://www.cpro.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160759cecaafc2---wuxat.pdfIn PDF document text
    • http://ristorantebiscione.com/userfiles/files/73726123324.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/xurawojudodi.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/e9cac8b33ef48f8be15cf07135a6d962/gobuvotakiruxitugupog.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/67317308360.pdfIn PDF document text
    • http://solemarservizi.it/userfiles/files/xumapokuwolebeduduwinese.pdfIn PDF document text
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/viberokijivi.pdfIn PDF document text
    • http://chetaomaynganhnhua.com/uploads/files/64291680501.pdfIn PDF document text
    • http://call.ae/wp-content/plugins/formcraft/file-upload/server/content/files/160ad10c84de4c---zobizogazizopisukekigu.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8655daf68---jusekazepakitisogameloveg.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///bevabukidimez.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b731eda32d0---75565704361.pdfIn PDF document text
    • https://maintogelonline2.com/contents//files/nowedefumakavanowesinuj.pdfIn PDF document text
    • http://theclubburger.com/uploads/files/japipejup.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bd3b24992df---wasadopedigirarimufepax.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160997ef7a2e5d---gaxanuduxuworakofinefite.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16118a2fb97d9d---16162949894.pdfIn PDF document text
    • http://maksimetall.ru/files/74022247844.pdfIn PDF document text
    • https://orsam.org.tr/paketler/ckfinder/dosyalar/files/46244633153.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609ebab1e98f4---vafovufanodede.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/17070866928.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/ni06c1p7aqi50r8jdd068t6loc/977341331.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=relapse+prevention+strategies+worksheetPDF 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_off0000e65e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65E 10820 bytes
SHA-256: f7bbb3a5b2a7124b64c26a9b60720b68452d7504c71b2626510490b7efcbe5a2
font_01_sfnt_off0000ff59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF59 17536 bytes
SHA-256: 1e7eed547e5305fc126ba2554ac58d7c8d89840a211a51042316aaf17b6e8fe2
font_02_sfnt_off00012cd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CD0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1