Malicious PDF — malware analysis report

Static analysis result for SHA-256 191a1956f8a1864b…

MALICIOUS

PDF

68.9 KB Created: 2021-09-28 01:49:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: dea42a681e3d1527977c43b8f568610e SHA-1: 31cbd9cd8629912d3705cb10760865e2a187ac61 SHA-256: 191a1956f8a1864bcb9e1ee6671cd2900e050f496c604aa25d0c83d4f55ceba8
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on compromised websites, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, but the structure points to a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://essuances.com/ckfinder/userfiles/files/zovomararenepufofana.pdf In PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/b964d754bc60326de03ebf5e6415a02f/67645477787.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/36526232565.pdfIn PDF document text
    • http://www.hotelrestaurantmacarena.fr/ckfinder/userfiles/files/74536519552.pdfIn PDF document text
    • http://silverspringabw.com/uploads/files/87514849166.pdfIn PDF document text
    • https://pesonabali.dswip.com/ci/userfiles/files/86199800217.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/dalugevagotovevuwi.pdfIn PDF document text
    • https://zohopinler.com/calisma2/files/uploads/87926869594.pdfIn PDF document text
    • https://raovat72.vn/uploads/news_file/zesadorisokagelojapatazok.pdfIn PDF document text
    • https://karaari.leaddeehub.com/userfiles/files/lekuzatukupuwafe.pdfIn PDF document text
    • http://bisnismedsos.com/userfiles/file/belofozinemizedexopit.pdfIn PDF document text
    • https://steammining.com/userfiles/file/wuturukukijapanitelujox.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/59179445913.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-01-04-53-16-51.pdfIn PDF document text
    • http://bkmarine.net/ckfinder/userfiles/files/1632322034.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/c2evmkupni68kjuv61nqgei22g/mebasapokusu.pdfIn PDF document text
    • http://www.santabriganti.org/admin/ckfinder/userfiles/files/goranavomufavomuluwixoxi.pdfIn PDF document text
    • http://konberdbio.com/upload/files/wudanuxuxejupe.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/xudisidotizobukaz.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140e40f7178c---zefagamowu.pdfIn PDF document text
    • https://sikdercollegeofpharmacy.com/scp/ckfinder/uploads/userfiles/files/bowufamoxifuz.pdfIn PDF document text
    • https://landi-bg.com/images/file/91839730769.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/8c9f89fdb76df8165927768f1bba29cf/zakudexasar.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/nezelibakunijoronowogo.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/98321678557.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=mobile+cric+hdPDF 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_off0000b0ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c8c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C4 10068 bytes
SHA-256: 4bf6b0bd434357e2c0bf78a6b4d0758b5c88a81accd6d46aeeb9953a8d27a97a
font_02_sfnt_off0000df32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF32 15032 bytes
SHA-256: 773c0003fbe83a781a1adc0f6311a9eae7fddaec76845513d5cddbd9c77aff81