Malicious PDF — malware analysis report

Static analysis result for SHA-256 836de0c1aeda4fd4…

MALICIOUS

PDF

96.5 KB Created: 2021-06-24 06:25:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 774effdb277e72d8c70cee10ee671370 SHA-1: 5bb9f1834404f7e3b7a6da9050f8858106be83c4 SHA-256: 836de0c1aeda4fd4493feb1572b68629ac3971b18329834349ced72fb786ab75
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'SE_FAKE_CAPTCHA' suggests the document displays a fake CAPTCHA to trick users into executing commands or interacting with the document, likely to download further payloads. The numerous embedded URLs pointing to compromised CMS uploads and disposable hosting reinforce the phishing and link-farming nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://nomylo.ru/uplcv?utm_term=korean+drama+tagalog+dubbed+full+episode
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/e777ba13c869e2cfc994a127d9abb6c9/wuputubameriduv.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/6e94623e5d55e836e05087081507384a/wojan.pdf
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098a0de1dacd---wisamaga.pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16079ac6ae9a33---farabuwigolufajelebog.pdf
    • http://yourtruck.be/upload/ckeditor/file/55920741027.pdf
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160823ce05df66---50403586831.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a9d919868---favuzawinanelawesaxewu.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/fcfteumkm4i6mifl27a6ng9cjd/96194127276.pdf
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b74f6048689---70969565913.pdf
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/d3d7d9aa48135a6c388dd7c81ae358f2/bekumezoravajuwanarix.pdf
    • http://zovsh.com/Uploadfiles/files/1396070034.pdf
    • http://morethancars.nl/uploads/edytor/file/94538386306.pdf
    • https://igruppe.no/ckfinder/userfiles//files/neterojetuxozetupisidaw.pdf
    • http://alibabashipping.com/userfiles/file/tazozijegijokudozef.pdf
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093aa560ccfe---86662256213.pdf
    • http://ajarnveerapong.com/UserFiles/file/mirisakamezixej.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012919.bin
e741dccf92b329c5364748a1ca3d076b8df29dd7f9d4741e5dab1557ac51f55f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12919 4244 bytes
font_01_sfnt_off00013811.bin
6acdb4e7df1dc080b0456f033a0dd9f30f5d274b2404e51500c932defc2d948e
pdf-font-stream PDF embedded font (sfnt) at offset 0x13811 5472 bytes
font_02_sfnt_off00014a95.bin
27d6da67e55fc00e535e3de85ca229e3b05a2c880f79b8c85fcedb2ee495aff7
pdf-font-stream PDF embedded font (sfnt) at offset 0x14A95 13168 bytes