Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3f9c521d2fa7812…

MALICIOUS

PDF

70.8 KB Created: 2021-09-18 21:33:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 06ef713b53a927f252be4494ce8aff80 SHA-1: 8693be3284e3fdc622ac95c70c52fecaacc8a3bf SHA-256: d3f9c521d2fa7812a56f9ed2d6c6533250118da029973cc20c97aa0adaf3f423
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of external URIs and link farms points towards a spearphishing attachment as the initial access vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=free+vpn+telegram PDF link annotation
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/86852923509.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/4848346503.pdfIn PDF document text
    • http://videofilm-tv.ru/content/File/bonusitafimifafodafelorip.pdfIn PDF document text
    • http://laskod.hu/userfiles/file/80935050619.pdfIn PDF document text
    • http://myappartement.de/web/editor/files/6263369470.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/rivudutem.pdfIn PDF document text
    • http://nfrostov.ru/upload/files/74011645796.pdfIn PDF document text
    • http://ambvet-trefontane.eu/userfiles/files/sozimuzepapisagasanafolip.pdfIn PDF document text
    • http://conhantaoankhanh.com/webroot/img/files/5222442188.pdfIn PDF document text
    • http://integrotech.com/zdjecia/file/24573623657.pdfIn PDF document text
    • https://omprintandpack.com/userfiles/file/tozodar.pdfIn PDF document text
    • https://elsa-daulte.com/ckfinder/userfiles/files/vulinaketuxelur.pdfIn PDF document text
    • https://mimpi1pusat.com/contents/files/40812453567.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/14234384040.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/r25g6thucm69efo75u67ibik1r/gapowedetuxevebunefipew.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/33212484676.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/93755695659.pdfIn PDF document text
    • http://hasdeu.md/data/userfiles/files/befezoj.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/zulufisox.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/15907561231.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/949a78e4d1f61019f489572465c7afc4/68640144699.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140751c7e9bf---gujuboparanuxan.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/161309dd71d40e---gujabejuxazizik.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/dojojupilemu.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/23999936161.pdfIn 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://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_off0000b738.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB738 10256 bytes
SHA-256: cb307f0ce0c07e088b2b0b89484ebbdb82081d3e2858183f92a773804eeb7f43
font_01_sfnt_off0000ce3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE3E 15564 bytes
SHA-256: 9ea836ede949428d69639c5e32619514aa668ed58ddd33a8309940d38bec1f77
font_02_sfnt_off0000f5bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1