Malicious PDF — malware analysis report

Static analysis result for SHA-256 8958d4ea6316df1b…

MALICIOUS

PDF

74.8 KB Created: 2021-09-13 11:31:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2937aa74e5c3340b25f920bcb8efd9d5 SHA-1: 5fcae210f4e62bceeeaad79af42557e571ff27f8 SHA-256: 8958d4ea6316df1b163d01c5a5584a7862e803780ee3471381d67ca1504644a6
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs that form a link farm, with several pointing to potentially compromised WordPress sites or disposable hosting. The primary function appears to be redirecting users through these links, which is a common tactic for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://angarakshaksecurity.com/userfiles/file/liditegumu.pdf In PDF document text
    • http://tetrafluoro.com/upload/files/nugetuwarel.pdfIn PDF document text
    • http://77owship.netsociality.com/upload/files/xefulisokezotan.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/xusaxel.pdfIn PDF document text
    • https://artistaone.co/userfiles/files/mabetasosujuzirupotagibi.pdfIn PDF document text
    • http://daegyung.kr/userfiles/file/20210910150913.pdfIn PDF document text
    • https://a-1commercialkitchenservices.com/ckfinder/userfiles/files/52697921501.pdfIn PDF document text
    • https://automatisme-portail-bordazzi.fr/userfiles/fichiers/62961165818.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613614407719e---34558065659.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/fujapof.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/lb094ghbl9d29cge3r9d7l4nf9/fodikafunorudokutonet.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/81363437211.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/30565905577.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/61604532832.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612f991a61dcd---23979756373.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1523e5eb4---mapogituzowato.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/61265378435.pdfIn PDF document text
    • http://pitchdecor-construction.com/user_img/files/futovinekiweketixadibiwi.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c91d2d312---38769566743.pdfIn PDF document text
    • http://avandcie-energy.com/ckfinder/userfiles/files/1257945702.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/161344f9e9d257---69746124894.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/70d8da3a943b3d1ce9edd11e7efeed0c/dikew.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/59649474555.pdfIn PDF document text
    • http://dpholding.ru/uploads/files/mepemumafeze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=android+attendance+system+app+source+codePDF 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_off0000c214.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC214 10824 bytes
SHA-256: 64ed2fa55142297688ca8d73b0325b2f5317488a3b84767e111c911420f4f980
font_01_sfnt_off0000db0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f31f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF31F 16444 bytes
SHA-256: b24a66b24f92e3a03fe899215ff6354f1999708af37738fa190e8a9b54b617f7