Malicious PDF — malware analysis report

Static analysis result for SHA-256 36b415835c5c4468…

MALICIOUS

PDF

68.1 KB Created: 2021-09-25 13:57:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8b042f5b1a2d072f5fa2af1f815c10b4 SHA-1: 0391e55f800430de35979e010a550edc188d3acb SHA-256: 36b415835c5c44681d06d259798bd171e2c65490de9639b9edc7bdb0636897ab
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised websites 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 attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://ksmt.edu.np/assets/ckfinder/userfiles/files/91606113130.pdf
    • https://art-eria.pl/mandarynka/pliki/files/9156760651.pdf
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/889e2020ee1ff456b0434f6a2076ce06/winiwukegogapum.pdf
    • http://vattucongtrinh.com/userfiles/file/14580353192.pdf
    • http://allasclub.com/campannas/file/34186066621.pdf
    • https://xyoaa.org/sites/default/files/files/wokaruvijamegojorabiv.pdf
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/1632085044527.pdf
    • http://ty6600.com/userfiles/file/56906548955.pdf
    • http://freeski.hu/freeski/file/40871748248.pdf
    • https://olgunbey.com/upload/ckfinder/files/wasoxuvarajisaxo.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/faeafb47982e1b82a73e90fb347d4d97/gubogazilizojev.pdf
    • https://esvigo.com/upload/files/pibubipedov.pdf
    • https://okud-istra.hr/userfiles/file/57764162469.pdf
    • http://yuemeism.com/uploadfiles/files/63006232993.pdf
    • http://tiwtactic.com/userfiles/files/latisipezixaroka.pdf
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/38774474786.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e07ce9076---98422063769.pdf
    • http://e68momo.com/shopadmin/upload/files/zubojejesotejavezuk.pdf
    • https://solidpractise.com/files/userfiles/file/lewisobofofifu.pdf
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/77811980821.pdf
    • http://encino.kopanramen.com/uploads/files/87908643073.pdf
    • http://tongshengchem.com/ckfinder/userfiles/files/rifopujemamokipojaxogur.pdf
    • http://24cvety.ru/upload/files/fisafilageliron.pdf
    • http://elcwma.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/puxagobifetanafamikozokur.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=android+apk+pc
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000afbf.bin
855058701c3caa0f4390d0f1ccec1f1f6642a7802398fe2d4dc1fbb10f1097d1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAFBF 14600 bytes
font_01_sfnt_off0000d48f.bin
b13e6f7fb911b276a93abad7d29b961b8a335e0dcdb2389f67bde468d903248e
pdf-font-stream PDF embedded font (sfnt) at offset 0xD48F 10136 bytes
font_02_sfnt_off0000eb46.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB46 16792 bytes