Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6a59e8b4335b176…

MALICIOUS

PDF

83.6 KB Created: 2021-09-10 13:27:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 852d5a04d2bead292581d0dec46446b3 SHA-1: f5009072d3bd4a1cef3b0bd106f9db373e9045ab SHA-256: d6a59e8b4335b17647efdcd6371eff468af2c80d033f38e9be51112943db5c90
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to other PDF files hosted on compromised websites, suggesting a link farm or SEO poisoning tactic. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery mechanisms.

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
  • 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://shoppingplanet.ro/ckfinder/userfiles/files/porulimobu.pdf In PDF document text
    • http://lustigersteirer.at/userfiles/file/vujewufedupowu.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/ca7a5994fbc1151f0f37ae2b5e6268e3/43079829790.pdfIn PDF document text
    • http://pure-chiral.com/upload/files/xepatixiposa.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/fusipuvamoguna.pdfIn PDF document text
    • http://reversetheclocknow.com/ckfinder/userfiles/files/59304791489.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/malivalunuwogizaruji.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/30542404143.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a429ddc570---mopavimof.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130461a05324---busizi.pdfIn PDF document text
    • http://linker-apps.com/files/6960445920.pdfIn PDF document text
    • https://aiaciran.org/cache/fck_files/file/retuterojunazeluwozijikip.pdfIn PDF document text
    • http://quesnelbusinessnetwork.ca/userfiles/file/fafil.pdfIn PDF document text
    • https://nitm.ac.in/nitmeghalaya/ckfinder/userfiles/files/39876151538.pdfIn PDF document text
    • http://www.kymkarajok.net/tiedostot/files/73249810185.pdfIn PDF document text
    • https://barcelonacentromedico.es/files/galeria/files/61776398760.pdfIn PDF document text
    • http://elma-itc.ru/!upload/files/walijajuxetaf.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/28308548274.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/43903616570.pdfIn PDF document text
    • http://suriyedostlukdernegi.org/image/files/65873391036.pdfIn PDF document text
    • http://stefani.cz/fck/file/21383300376.pdfIn PDF document text
    • https://vidaleve.net/ckfinder/userfiles/files/kitaxeviz.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/xisilev.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=play+psp+games+on+androidPDF 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_off0000e230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE230 17876 bytes
SHA-256: 3362e2f7dec17b671b5b4199d5013cac7985a37e2c48c05f9211363e9388e7cf
font_01_sfnt_off00011039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11039 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012850.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12850 10752 bytes
SHA-256: c99bc6d225a9fdf137d32221b73f2a1839a3ac11377ce660a6a126416ef60a0a