Malicious PDF — malware analysis report

Static analysis result for SHA-256 099436a4189af6c0…

MALICIOUS

PDF

89.7 KB Created: 2021-06-26 14:18:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2ffb9a556228adfc34170c114b32c881 SHA-1: d328a182944834aceb0fe449cc1969b81cabbc41 SHA-256: 099436a4189af6c0cb71dbcf98520f3140cb055ba6a42561b0d3f189c5d23ef3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous links pointing to compromised WordPress sites, suggesting it is part of a link farm designed to distribute malware or facilitate phishing. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8f7fc46b3---jozedofenevonozidevizuvo.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2c3c6dc689---firisafituvunaxeran.pdf
    • http://talleresjpg.es/img/file/93406024514.pdf
    • http://valaptop.com/ImagesVA/file/walaxanel.pdf
    • http://reclaimsplus.com/wp-content/plugins/super-forms/uploads/php/files/ff90d912bb236e5f0d4e94f85af2a963/49300977480.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b35df82513---49755229008.pdf
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/40baa40d9abbc1f6bca331d9e4f9af7a/58179419686.pdf
    • http://hayatteknoloji.com/webimage/file/20561853391.pdf
    • https://nothingbutsafetyglasses.com/userfiles/file/76074889537.pdf
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/8796b9ab120ed201eea93e3c42260bcc/2912919667.pdf
    • https://taevlingar.se/images/pages/file/90451137432.pdf
    • https://amatnieks.lv/pictures/image/36101891094.pdf
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/dmsd9ohcb80372h1pag3a0h1el/xapidaw.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/e12989e58b13543af227f815165dd805/lajufojuteroxodujume.pdf
    • http://wonikqnc.com/upload/editor/file/1624587222.pdf
    • https://alnahamgroup.com/userfiles/file/fozusesuwetofu.pdf
    • http://riversedgefm.com/files/file/57614593888.pdf
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608e4eecbabcc---fuvilonugoguwe.pdf
    • http://abwcoliseum.com/uploads/files/39228115986.pdf
    • http://guides2alpes.org/uploads/file/91649425432.pdf
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160986f2eb2caa---66933813300.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=four+theories+of+language+development
    • 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_off0000fa70.bin
d99efff8208084f1c93facb8235ebe121fc19425620f3daef7acf57135ec2a8b
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA70 17032 bytes
font_01_sfnt_off0001269d.bin
000b4f0b6c08a51ff6f031770aa176625976cbb8804571ed27e36cb4fc359c2b
pdf-font-stream PDF embedded font (sfnt) at offset 0x1269D 11088 bytes
font_02_sfnt_off00014015.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14015 16792 bytes