Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c8a64b981455fb8…

MALICIOUS

PDF

101.4 KB Created: 2021-09-12 03:11:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cbfd8b88829f844309e02dd985155a3a SHA-1: 1683f00f9aae562359495d93161b22fa0396efa7 SHA-256: 8c8a64b981455fb8a410234199a45e88125d415bf1f05f14ec2bbf3e49a2647f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed for malicious redirection. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is being distributed through these links. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://thanhtindesign.vn/uploads/image/files/14213226579.pdf
    • https://sluganarodu.org/userfiles/files/mokexadavovadidamen.pdf
    • https://tour-paris-guide.com/cite_imgs/file/23580940099.pdf
    • https://faresaldabbous.com/uploads/files/83015980673.pdf
    • http://cabanagarden.hu/editor_up/kutogemivuvexowa.pdf
    • http://terredellamagnagrecia.com/userfiles/files/fizanab.pdf
    • http://loadcell.vn/Images_upload/files/zuwevuxegan.pdf
    • http://quantri.thaisonpalacehotel.com/upload/files/mixeguboleluxaf.pdf
    • http://xn----itbbfrdrdbd4bgy6gi.xn--p1ai/webroot/files/files/20729473724.pdf
    • http://espicycooking.com/files/file///mowoxosafowita.pdf
    • http://gfzgt.ch/upload/file/35421336060.pdf
    • https://kildevangen.dk/files/sizimaregufamid.pdf
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/mukedoxobol.pdf
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138891f22725---galazadafizolubad.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/i0fqtiqbcu73mcb92k9i011uh1/loruginuvudojovejatubow.pdf
    • https://szabolcsipeter.com/userfiles/file/27967706613.pdf
    • https://ghnservizi.com/file/dolotumixuxamemiz.pdf
    • http://idolyokocho.com/js/ckfinder/userfiles/files/98378373940.pdf
    • https://xn--lenachatka-57b.pl/uploaded/file/nefosigiripidukelej.pdf
    • http://hamyarsanatco.com/ckfinder/userfiles/files/58908247528.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/d3a94800fd5eb753c3f02bfd72fe6697/bamuwonojewezarudiligi.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135238958ed8---84124698583.pdf
    • https://namratalakhotia.com/userfiles/files/99286144053.pdf
    • http://shopcode.ru/uploads/file/xudimelesukixamugi.pdf
    • http://duhochoangthanh.com/upload/files/99633149332.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=piccolo+and+gohan
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011f27.bin
16856cb2519c6048724209cfa184e11fcbcb985a7d391c08b56d802bbb0115dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F27 22160 bytes
font_01_sfnt_off000159cb.bin
76b954ed09eb5dc368ad2294e817f2a7e6f6e948fc792497bf6f8b8e37a0f362
pdf-font-stream PDF embedded font (sfnt) at offset 0x159CB 10152 bytes
font_02_sfnt_off0001701b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1701B 16792 bytes