Malicious PDF — malware analysis report

Static analysis result for SHA-256 aec937c1bd94e19b…

MALICIOUS

PDF

75.9 KB Created: 2021-09-07 22:34:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7f6d20698ef4403013b8cfa6fbac2e16 SHA-1: a4db52d679193c9e4915d1e27e3d7f176232e3b1 SHA-256: aec937c1bd94e19b28ce605f99d1e4a6d75710550c4f0ac7cf7905e48a8947de
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, directing users to numerous external websites, some hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 http://rszm88.com/upfolder/e/files/20210821035553.pdf In PDF document text
    • https://banderlogclub.ru/Files/file/55690630504.pdfIn PDF document text
    • http://csp.hu/editor_up/rolif.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/14044330670.pdfIn PDF document text
    • https://spbmworld.com/anaeter_capital/siteadmin/userfiles/files/77036013355.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es//ckfinder/userfiles/files/26519295332.pdfIn PDF document text
    • https://hojoairport.com/images/file/lepexogunuregasiwe.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/80714156085.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b070f6e4fd8---79990620416.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/79575479726.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/8276f6eb1a4aacd7dd58fd977b011d55/boredob.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/towasowemipoduweg.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/lopaforobawuritona.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bf5a331a692---535035304.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/8404881502.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/dinutubuxujakifadilawumir.pdfIn PDF document text
    • http://udaybharat.in/ckfinder/userfiles/files/tejoxi.pdfIn PDF document text
    • http://aliguoriarchitetto.eu/userfiles/files/902326190.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c085bf1c6bc---wikosizovufozofopuwu.pdfIn PDF document text
    • https://www.premiumtrade.ro/ckfinder/userfiles/files/jiletafejajugil.pdfIn PDF document text
    • http://elandtour.com/FileData/ckfinder/files/20210709_92CEB058C80900E5.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210725_C40CF216D5056A8D.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=reichert+tonopen+service+manualPDF 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_off0000c368.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC368 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB7F 10852 bytes
SHA-256: 4eba6146b25d1af34309582ed5a8192b4cbd0b3b1489240e9f715f8eefb6d714
font_02_sfnt_off0000f460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF460 17912 bytes
SHA-256: d7c547e6f7f311c0ad6e0a9a879274693a6b0745d31ea5fe196b1a9eb4591673