Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c6fa33a440f9bfd…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 15:18:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0a28bd123128b63d3441524c908f6bab SHA-1: 64a3fd94f91bb48a65aaeeb818684d61a05dd6a4 SHA-256: 5c6fa33a440f9bfd5309351bb86011d873730d5fdef272af693508543ab24b30
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://allytemp.ru/uplcv?utm_term=modify+an+apk PDF link annotation
    • http://ocean-ex.com/images/blog/file/dobodironezidisijetivuli.pdfIn PDF document text
    • https://inprovitcolombia.com/ckfinder/userfiles/files/76853234898.pdfIn PDF document text
    • https://ausztriasi.spawellness.hu/upload/hirlevel/files/11701072250.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614360b650e0f---zagevur.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/68684534862.pdfIn PDF document text
    • http://sbnjl.com/userfiles/files/83628938040.pdfIn PDF document text
    • http://hfengly.dk/skoleportalen/userfiles/file/22120560734.pdfIn PDF document text
    • https://saptabangunmanunggal.com/indomobils/upload/file/23574734359.pdfIn PDF document text
    • http://escritacontabilidade.net/fotos/news/file/31840614726.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/161418a17dca96---tapobi.pdfIn PDF document text
    • https://www.savininkai.lt/ckfinder/userfiles/files/togimuverozilogow.pdfIn PDF document text
    • http://machinesupplier.cn/data/product/file/202191_231115_933.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/vetaxexasenabivabezevoxi.pdfIn PDF document text
    • https://birsamundapark.in/userfiles/files/texuwigeketa.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/82155244573.pdfIn PDF document text
    • https://sunkamalzemecilik.com/userfiles/file/tikasanomojeda.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/51ccbjamn4cfdpap0a2jq3lklj/weweveba.pdfIn PDF document text
    • http://sksound.com/userfiles/file/2275542552.pdfIn PDF document text
    • https://posh.hr/files/lovexoduke.pdfIn PDF document text
    • http://kd-council.com/upfile/files/85509336798.pdfIn PDF document text
    • https://gionggiacam.gagiongvitgiong.com/ckfinder/userfiles/files/kajijisigax.pdfIn PDF document text
    • http://wedding-box100.com/uploads/files/202109100223357987.pdfIn PDF document text
    • http://eska-lift.ru/userfiles/file/pibegan.pdfIn PDF document text
    • http://iburgisidimarsala.eu/userfiles/files/palekujaf.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_off0000ddf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDF7 10148 bytes
SHA-256: 3a36b428d12271550745492373c5095711fa64d2d2ea47ea0345b6188b853727
font_01_sfnt_off0000f4b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B3 17460 bytes
SHA-256: 05cf18eb370066121274ae06c0884bb4840c45b322f2ab4a04b380e9730ce5d0
font_02_sfnt_off00012206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12206 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1