Malicious PDF — malware analysis report

Static analysis result for SHA-256 f03a669996201aaa…

MALICIOUS

PDF

76.2 KB Created: 2021-09-18 02:37:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 84e0f797a5c1d95372c108ea11deb891 SHA-1: af4646a7e14f06ddb67cdb2a54b5d563c014fdf4 SHA-256: f03a669996201aaa86d2e71e1421a78be200520606e80ac1896a85090b720a8e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, many of which are part of link farms hosted on disposable or compromised domains, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF's primary function is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://coretry.ru/uplcv?utm_term=wordly+wise+3000+book+7+answer+key+pdf PDF link annotation
    • http://papienbanana.com/user_file/file/doluf.pdfIn PDF document text
    • http://cantinachitarra.it/userfiles/file/25071602394.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/89239281354.pdfIn PDF document text
    • https://cfaegaianascente.pt/portal/userfiles/files/9736269096.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/25141434840.pdfIn PDF document text
    • http://cungcapluonech.com/upload/files/72643918405.pdfIn PDF document text
    • https://voicelux.ru/wp-content/plugins/super-forms/uploads/php/files/3311c5f2de62e6ee68078fbc42310bec/37821837017.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/japezokulegenamuno.pdfIn PDF document text
    • http://amunt.madteam.net/ckfinder/userfiles/files/zujuxamaxinexelokojimanu.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/81421020015.pdfIn PDF document text
    • http://princeverma.in/uploads/files/zexibiwodowukewapiw.pdfIn PDF document text
    • http://studiocalderini.it/userfiles/files/12258907524.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614505f78ec21---fatalibamokafugu.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/luwox.pdfIn PDF document text
    • https://petpetmates.com/files/editor/file/64203610241.pdfIn PDF document text
    • https://ijieet.org/ckfinder/userfiles/files/vefewajejuzubisavuzibi.pdfIn PDF document text
    • http://gorsilawfirm.com/userfiles/file/10462221966.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/gubujaz.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.net/ckfinder/userfiles/files/17546170864.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3067dfc19---rorasususitivusefufedafo.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_off0000c74f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC74F 16484 bytes
SHA-256: 94bc756c2004c90cf9495fddbf66db03b64ac24644cb5d5d7ee553eb6d832b3a
font_01_sfnt_off0000f19d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19D 11160 bytes
SHA-256: 23027684769873b025473b1e799123adaf023765cd954d30225c65a19012ae0e
font_02_sfnt_off00010bb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1