Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a87ac723689b305…

MALICIOUS

PDF

85.6 KB Created: 2021-06-13 09:07:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 83b0fd9f5bbab93872e4ef7b51d5eb4a SHA-1: b123b9308abd3b04ae54557ee13bfca4b1488c11 SHA-256: 5a87ac723689b3050944aa7e219c1c084c7c88bef24379d9077ee2a816de879c
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites, many of which are part of link farms designed to obscure the true destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading malware disguised as software like 'mortal kombat 11 apk obb download'. The presence of multiple external URIs and link farms suggests an attempt to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crysiq.ru/uplcv?utm_term=mortal+kombat+11+apk+obb+download PDF link annotation
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/qq73a628peb1srqrhh43rhjonu/84413950627.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/57393080889.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/70648215708.pdfIn PDF document text
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/vowigevamulokezu.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/cbb23e21f80f105fb5e5babca71fe68a/sexoxunesidoxoli.pdfIn PDF document text
    • http://albertopizzetti.it/userfiles/files/mofewaf.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f40ffaf04e---86304693683.pdfIn PDF document text
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/0qs2tfb91tvhsbmor388eqonug/13071214377.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/2ae10279815a02d8a12ff2d3c4388894/76436572991.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16072094693731---mafemazivibobape.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bfed68e434c---78903666584.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d950e2e8fe---funoduti.pdfIn PDF document text
    • https://bednidhitraders.com/userfiles/file/bexepupere.pdfIn PDF document text
    • https://gloriouz.in/ckfinder/userfiles/files/79748541577.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/579dd18f866de19feeb26dd4f52d7b7a/16607539881.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000104c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C0 3112 bytes
SHA-256: 6722f2fc6481e457481ec26e567bee5ee8ff2691934f962887e0ecfb2c8f6d20
font_01_sfnt_off00010ffd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FFD 5280 bytes
SHA-256: 9de1767db49e9bb5e8aa1f4a82e06bf95a70a2fca787a6e9c3c163358cf8c458
font_02_sfnt_off000121f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121F4 11004 bytes
SHA-256: e4ebec4e9c321fd792534a9d468065dc63554dbe67f310e135a7f24985cec31f