Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1719c372c2cf61f…

MALICIOUS

PDF

88.5 KB Created: 2021-09-29 07:48:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 91ccf236943518bce12d658b13a921f3 SHA-1: 027cf4e065a284657b05fd7aebb99fa0619bb978 SHA-256: c1719c372c2cf61f5b028df45dfbea4f5078c97e4f690b66ee68a8a21a4771d0
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to potentially compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, while numerous, are the primary indicators of compromise, likely serving as redirects to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://hantechwelding.com/userfiles/file/2021090823561873499.pdf In PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/rojuguzusanoxutovax.pdfIn PDF document text
    • http://studioambienteterritorio.it/userfiles/files/mozepunujabatorup.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/28731293569.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210902111834.pdfIn PDF document text
    • http://yuhongzg.com/d/files/65396744711.pdfIn PDF document text
    • http://abwlanham.com/uploads/files/zotefisu.pdfIn PDF document text
    • https://myreply.mobi/snappshott/editor//file/ganebipuxixove.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613df1668dc47---leperadowejigofiw.pdfIn PDF document text
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/depaxor.pdfIn PDF document text
    • https://clinicscrm.com/img/files/fibivurijezurivanijif.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/krulqschs42c3mfda22jm6obd7/tojelivupibiniwis.pdfIn PDF document text
    • http://emailreceptionist.net/userfiles/file/xugafuvade.pdfIn PDF document text
    • http://dominant.name/userfiles/file/busadujalexoseloxugu.pdfIn PDF document text
    • http://jcnjl.com/userfiles/files/59318096996.pdfIn PDF document text
    • https://onutglen.com/caningest/images/file/59650137019.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/zikuxu.pdfIn PDF document text
    • http://tipsclubcr.com/campannas/file/burerizedamo.pdfIn PDF document text
    • http://mikomisushi.com/uploads/files/8378329903.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/baradubevawusabiji.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/24u0g8af3pi2h3q83mnkclpm41/tumamagidebiko.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1614f0fae399f6---9249756047.pdfIn PDF document text
    • http://msnladyboy.com/ckfinder/userfiles/files/vogetefedisodivomeduvuke.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/99888479024.pdfIn PDF document text
    • http://bio86.fr/userfiles/fichiers/58330424142.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/30864183212.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=jak+utworzy%C4%87+kopi%C4%99+zapasow%C4%85+androidPDF 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_off0000f1a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000109ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109BA 11232 bytes
SHA-256: 6ae5f354c6ddd04be3e2618e910908a2d07c733b0b04920b70658cf2763f61e2
font_02_sfnt_off000123ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CE 18428 bytes
SHA-256: 5d9150fbf83b76c44df4fc07c7c6a0a0d8d5edc181d4b2ec570b6d7ed9c73fc0