Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4cbbc75913e83a7…

MALICIOUS

PDF

81.1 KB Created: 2021-09-19 23:52:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 05623497074c4024e7549e2ba006eca7 SHA-1: 5ef5761e79dfec0840988aab5b496e203a9a0b62 SHA-256: c4cbbc75913e83a754557ffd4e3f34f4cd9ff9c4f94972d718f79c10a8f8c031
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://ketchas.ru/uplcv?utm_term=o+melhor+jogo+para+android+do+mundo PDF link annotation
    • https://takarasushimn.com/userfiles/files/pifuje.pdfIn PDF document text
    • http://hidrometa.com/images_upload/files/jijenigaretasuboxef.pdfIn PDF document text
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/41561331136.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/tajijotufidivetiwu.pdfIn PDF document text
    • http://prinsart.ro/uploads/files/xewetatilelo.pdfIn PDF document text
    • http://suvenirzp.com/uploads/files/40075134085.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133985fbe2e4---66918378757.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/rkqlrdgde3b9lf4f5dltjuq0e3/14901960813.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/90b263dc9c12d9dffabd028692b2820a/sidutefutubebanuxidoli.pdfIn PDF document text
    • https://nepalfinepashmina.com/userfiles/file/jikapudaregobirokefe.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408b215e4a4---60615733293.pdfIn PDF document text
    • https://xuanhongkhang.com/upload/files/84529156409.pdfIn PDF document text
    • http://ventss.ru/userfiles/files/26961290530.pdfIn PDF document text
    • http://packagingandfoodmachinary.com/userfiles/file/dimotatopu.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/9097832655.pdfIn PDF document text
    • http://mayinluatudong.com/uploads/userfiles/file/rulol.pdfIn PDF document text
    • http://inphuduong.vn/upload/files/jononudekojiwabakumodinu.pdfIn PDF document text
    • http://fazekaskozpont.hu/images/upload/file/sazuret.pdfIn PDF document text
    • http://xn--80aaaghhaztbcd1agjgbccsgfftf.xn--p1ai/pict/file/30884269316.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109060901264385.pdfIn PDF document text
    • http://architectureanddesign.it/userfiles/files/10419087928.pdfIn PDF document text
    • https://marlin-shop.ru/ckfinder/userfiles/files/3931915285.pdfIn PDF document text
    • http://www.gulbaharsigorta.com/contentData/file/59291251549.pdfIn PDF document text
    • 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_off0000d3e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E7 19380 bytes
SHA-256: 1d250525da881f6499556babc8fc6831aa5f7c5141b8893016a61decce8c8a3a
font_01_sfnt_off00010476.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10476 10828 bytes
SHA-256: 93ff711cdbc096ebe0253bcc9e316958b3eaff712550efcdff449b0fc468a905
font_02_sfnt_off00011ce7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1