Malicious PDF — malware analysis report

Static analysis result for SHA-256 27fe651abbfd9480…

MALICIOUS

PDF

71.4 KB Created: 2021-09-26 15:45:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 935246c50791938ac2d851967e4acfc2 SHA-1: 252390122d07ed5c803a1c402571990b5df06782 SHA-256: 27fe651abbfd9480a50586aa105d2d5adfb43b30c315dd8da14d18e69992657f
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of multiple PDF link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/limuriguwi.pdf In PDF document text
    • https://leonardscopysystems.com/home/leonards/public_html/ckfinder/userfiles/files/jexasaweleb.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/c96fa0e507522535983df06ecadb710d/jifixeviweresu.pdfIn PDF document text
    • https://marwaservicecenter.com/nbloom/fckuploads/file/36250990177.pdfIn PDF document text
    • http://gammatradings.com/userfiles/file/18747960416.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/vuzivuvaxulatupetufum.pdfIn PDF document text
    • https://expobar.vn/app/webroot/files/images/pages/files/jaworivabufidab.pdfIn PDF document text
    • http://aylincinarli.com/fckfiles/file/5568816127.pdfIn PDF document text
    • https://mcdelandes.ca/uploads/file/72068834779.pdfIn PDF document text
    • https://larioenergy.net/uploads/file/15680814714.pdfIn PDF document text
    • http://obkladlazby.cz/userfiles/file/rezerodofeweti.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/f05bd0dc3e7604bb1c1a7a93019cdf6e/58372823189.pdfIn PDF document text
    • https://markaoyun.com/calisma2/files/uploads/31013137602.pdfIn PDF document text
    • https://loyallcanada.com/editor_files/file/ropawarawonur.pdfIn PDF document text
    • http://griesvoegwerken.nl/UserFiles/file/jabolezuwid.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210926/file/16326497639705.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/36168708280.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/19844977285.pdfIn PDF document text
    • http://poledance-chrudim.cz/files/file/zotiwoserekutozuvisojexis.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/d2ddd785eb77a740b5dad3c9ed0c3f9a/janinudozojosusujesusuga.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/ua88bf0ekh78ns0l5gmss93fd4/90389399249.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-9-16/20210916153727821774.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-5/20210905235459719963.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/97966460197.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=flv+to+wma+onlinePDF 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_off0000b473.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB473 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC85 17512 bytes
SHA-256: ff4c806234f7a8dab53b11ba7553980229e573faff3db9ca47dc54fdcc793120
font_02_sfnt_off0000f939.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF939 10128 bytes
SHA-256: 497e58705c7dbc1c6295462202a73012eb0a032a2ea571d98eaf7bafb15c6284