Malicious PDF — malware analysis report

Static analysis result for SHA-256 88c446864e046459…

MALICIOUS

PDF

77.5 KB Created: 2021-09-05 13:53:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a49e6db6ed86518494b748b0a452000f SHA-1: f5793f0234bee548b3f84d21893a06c89e34fd8e SHA-256: 88c446864e046459626836eb0574aa2a120685794d19e38b7a9bf8f77ef1b5fd
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other potentially malicious domains. The primary purpose appears to be redirecting users to external content, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/f8d68380145e9fb64d85b970bdd5b9e2/5046266109.pdf In PDF document text
    • http://vladjurnalist.ru/archive/file/64767003393.pdfIn PDF document text
    • http://dichvugiayphep.biz/upload/ck/files/5045791708.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0adfbf2070---33705686365.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079ee47612bd---melazomasiwemuzexunikob.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/viruvarojoxudow.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/bikutuf.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/97544063050.pdfIn PDF document text
    • http://short-story.ru/upload/file/42667306755.pdfIn PDF document text
    • http://articolo17.it/siti//usr/foto/files/80637722215.pdfIn PDF document text
    • http://omegapizza.net/uploads/files/5751030947.pdfIn PDF document text
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/n65q0tq2vr9ue0urmjkc23adj3/sogirerudez.pdfIn PDF document text
    • http://tks-forever.com/upload/2021/07/06/file/wasobadoxixaga.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/49462638946.pdfIn PDF document text
    • http://hkt-optics.com/hkt/images/userfiles/file/rukeremupexipusisevofopet.pdfIn PDF document text
    • http://zulassung4you.de/bilder/file/39213624036.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099b85c99b18---36010567914.pdfIn PDF document text
    • https://tcremich.lu/files/files/93836262105.pdfIn PDF document text
    • http://honghuibio.com/d/files/rigupesixel.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/gixewafosasukosoruma.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/bovoxiki.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/a0e496b1c518a14e676369494c4b2989/povujebupuvekekuj.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4c8a892ab---jopukugifovuwofidejun.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3560bf5bd---44188542929.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=chronic+disease+epidemiology+and+control+3rd+edition+free+pdfPDF link annotation
    • 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://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_off0000c9c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9C1 11384 bytes
SHA-256: 8ccfacaaf5d3395a5f26a8e17b719047715bc00ea304c912cbe6523ec65d80a7
font_01_sfnt_off0000e43a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE43A 18152 bytes
SHA-256: ea976a0efb284423252b8f8526e46f2b1b861a1667f9caefe6d5cdc1f3dec107
font_02_sfnt_off000113b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1