Malicious PDF — malware analysis report

Static analysis result for SHA-256 f42b5c144d89cb0a…

MALICIOUS

PDF

75.6 KB Created: 2021-09-21 06:17:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6a76483744c9cce4d05bf22515bb098c SHA-1: 7b496e9ed1bac01e089ff99f1fa01849a027a0c5 SHA-256: f42b5c144d89cb0a7fc49d60fab406eca2bc86cc42d79186ebb4f56ba4c64fae
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by a ML classifier and ClamAV, detecting it as Pdf.Phishing.Trojan. Numerous heuristics indicate the PDF functions as a link farm, with many URLs pointing to compromised CMS upload directories or disposable hosting. The presence of 'utm_term' parameters suggests a phishing or SEO-based lure to drive traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://synerhu.ru/uplcv?utm_term=batman+ds+rom PDF link annotation
    • http://noticiascgnews.com.br/ckfinder/userfiles/files/subozuworuwoloda.pdfIn PDF document text
    • http://darec.sk/files/files/firodilunilivopovug.pdfIn PDF document text
    • https://illustrations.noche.fr/images/files/rapavugofivimufibajomuli.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16133961869fa5---93160365220.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/64571ef00ab958ddb73ad357cdba2f59/17861465526.pdfIn PDF document text
    • http://kotrackusa.com/fckedit_file/file///20210906_18_53_31.pdfIn PDF document text
    • http://grgct.com/ckfinder/userfiles/files/joredew.pdfIn PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/norozitubatitakakikixave.pdfIn PDF document text
    • http://royal-pizza.eu/files/file/43448832562.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/10495391471.pdfIn PDF document text
    • https://lmcmanager.com/ckfinder/userfiles/files/nutadisijumiwo.pdfIn PDF document text
    • http://apvn.info/userfiles/file/38214395480.pdfIn PDF document text
    • https://holcom-wd.com/webroot/img/files/23912008458.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/kileg.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/bajodawukemikefa.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614949d7ad5d6---4015030128.pdfIn PDF document text
    • http://5m-tti.com/uploads/image/files/31189269363.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/jasupelozosa.pdfIn PDF document text
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/mowuz.pdfIn PDF document text
    • http://yuanyoujie.vip/userfiles/file/forawubunu.pdfIn PDF document text
    • http://meskerjager.nl/media/files/31418902084.pdfIn PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/sujuluxivibu.pdfIn PDF document text
    • http://xutricolor.com/uploadfile/files/11147176264.pdfIn PDF document text
    • https://actorconseil.com/files/file/jifowepomegobagax.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_off0000c44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC44C 10192 bytes
SHA-256: 9700ff3d7454042bc171508c49567a5e3ae6140974a4de3209dc309e231d6fd0
font_01_sfnt_off0000db21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB21 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f333.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF333 17844 bytes
SHA-256: f0c70647702434e4753f0237eb35bb27a0351bac071e24af1b7a08c5acc812a1