Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c4fd352c0e81a91…

MALICIOUS

PDF

82.3 KB Created: 2021-09-03 02:58:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d11fe27754e355e987b4f7c39f153b8f SHA-1: c9937474c81c4e982120ba7e4fea57d81d3b3822 SHA-256: 0c4fd352c0e81a9136f4818785484d5bdf3f39ddf07a1dd6fbffc1973d4f782d
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm. The embedded URLs are likely used to redirect users to malicious content or phishing sites, potentially for SEO manipulation or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 http://amoy-art.com/Upload/file/48018916407.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/a5f987fe865709d45e7294a0b7dcf462/52581434715.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/llabhdfki5a20etrlglfuv0cbe/22555701033.pdf
    • https://bilegt.mn/userfiles/files/xadebukurexuwima.pdf
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/fp3iob5m5oodldlutrimihh8nh/69034096331.pdf
    • http://samuiluxurytravel.com/Uploads/file/pudikimejubuwemarak.pdf
    • http://amexeuro.com/an3_Uploads/file/lekojalidimadowavibimekuf.pdf
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d310b64d4---venenudaxa.pdf
    • https://acornschoolcharleston.org/wp-content/plugins/super-forms/uploads/php/files/5c6d858e0810699b4a36669ca4fb5347/80101235726.pdf
    • http://infinijewelry.com/userfiles/file/76652804273.pdf
    • http://rainbowcaterers.in/userfiles/file/50836086593.pdf
    • https://rubin2000-distribuitorshop.ro/userfiles/file/47937466931.pdf
    • https://noelex22.org/userfiles/file/35178725491.pdf
    • https://grancom.by/upload/docs/kurabugafavigeperow.pdf
    • http://satakantaresort.com/user_img/files/6496699097.pdf
    • http://buckleyfamilyofdarling.net/clients/0/01/017bf228c8331327bdfb67b1798bff80/File/82078603448.pdf
    • http://marinapogon.pl/upload/file/ramaraguxomizinopuwedu.pdf
    • http://titadoorbinhduong.com/upload/files/zolivimamilamubanexototuw.pdf
    • http://aescantabria.es/upload/fckeditor/file///73099379419.pdf
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ae75195b55---zawepukiliz.pdf
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/fidaoa7uch15fobsg6dfv7i0bo/dibijobelugomezelaw.pdf
    • http://markone-tools.com/upload/files/8395399021.pdf
    • https://aviseco.ro/userfiles/file/fumijuxegumo.pdf
    • http://musicupclose.com/clients/f/f7/f7c291dfb329fbc33054893077acf627/File/99924536947.pdf
    • https://alakharia.com/public_html/userfiles/file/tevapamasopinilusedozi.pdf
    • http://ippon.lv/uploads/File/fojilidipevow.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=advantages+of+prefabricated+construction+pdf
    • 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_off0000dd7d.bin
e198b9259ab511fcf7eaf62c3ccad68698ded7769057a5a51ded3e9840dbdc4e
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7D 11036 bytes
font_01_sfnt_off0000f6f3.bin
46b620b189ccc1e80d91b5d2a7bb83a254206935858474af1e889e52ec57be35
pdf-font-stream PDF embedded font (sfnt) at offset 0xF6F3 17116 bytes
font_02_sfnt_off000122ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x122EA 16792 bytes