Malicious PDF — malware analysis report

Static analysis result for SHA-256 e53f5547481ba310…

MALICIOUS

PDF

81.9 KB Created: 2021-09-16 16:33:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 0faf31756e0952825c36b3e38927106c SHA-1: 55c9b28fcb3ece591c30045c3ac1d2f8cf35ef03 SHA-256: e53f5547481ba31032b58e0706f3ee7b396098447f9acaba7d5619c77993b1e6
166 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier. The 'SE_CLICKFIX' heuristic indicates a social engineering attack that instructs the user to press Win+R or paste a command, a common tactic to bypass security measures. While no scripts were directly extracted, the PDF structure and heuristics suggest it's designed to lure the user into executing a malicious payload, likely via a command.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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://home-plast.ru/foto/files/motivuzo.pdf In PDF document text
    • http://poetische-malerei.de/web/editor/files/gatazamo.pdfIn PDF document text
    • http://www.valaisconsulting.ch/file/zafesolewironob.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/marape.pdfIn PDF document text
    • https://aspart.ro/ckfinder/userfiles/files/vorolabinafavajubo.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/gogowulebudim.pdfIn PDF document text
    • http://longtra.vn/userfiles/file/laniposolujalabigedifujun.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/lujidotemuke.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2b761f889---83916242149.pdfIn PDF document text
    • https://openkomm.yussfone-crm.com/userfiles/file/vewabedobovorusitegejef.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/5932781535.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/80648821764.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/xagukafo.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/9f51d031a68ff52eba7a0dc19a98c883.pdfIn PDF document text
    • http://quesnelbusinessnetwork.ca/userfiles/file/55451718974.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a99db9ed16---8240221379.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/pivalogizamufe.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/tenub.pdfIn PDF document text
    • http://abwingssuffolk1.com/uploads/files/xubilavudo.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/65805076341.pdfIn PDF document text
    • http://pronobile.de/catalog/file/xoluvimepuwawevomode.pdfIn PDF document text
    • https://receptabc.hu/images_banner/files/jaragufidifuxe.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/11676091819.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+receive+a+file+via+bluetooth+on+windows+10PDF 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://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://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_off0000da70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA70 11132 bytes
SHA-256: e9ff9552e340d7675334a352c4ee7c28e59497c11cad35a28651bb17be4ec285
font_01_sfnt_off0000f467.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF467 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C79 17356 bytes
SHA-256: 1c2e3ba4b60686b82109054855ef022f83613c8de9e4a33e3a1396ad1a8638f2