Malicious PDF — malware analysis report

Static analysis result for SHA-256 2539104df0b9053c…

MALICIOUS

PDF

73.7 KB Created: 2021-09-22 09:12:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ff4329571554093f3397f6b4773a0b24 SHA-1: cf5dd9574d6822f0369b7e2f99f5a13d54d17ee0 SHA-256: 2539104df0b9053cbe792fc67c4bfc9118ae4854d7423a47f77c72d3374e83ee
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple PDF link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://coretry.ru/uplcv?utm_term=rupaul%27s+drag+race+season+5+online PDF link annotation
    • http://vietsinphar.com/uploads/files/lowaveruzazazonesa.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/19429506091.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/52271039408.pdfIn PDF document text
    • https://tsegypt.com/file/lezulu.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1614948a149f86---25331305430.pdfIn PDF document text
    • http://interwork.sk/userfiles/file/dizowewixidawi.pdfIn PDF document text
    • http://herbwaterthailand.com/userfiles/files/kazujalexogudisezavutivi.pdfIn PDF document text
    • http://harryreichert.de/uploaded_pics/News/file/55965682462.pdfIn PDF document text
    • http://kxnjl.com/userfiles/files/fawajugiwetubonigamo.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/95699434004.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613ee969408fa---79410552728.pdfIn PDF document text
    • http://glassick.com/userfiles/file/vuzuzetozateniluvone.pdfIn PDF document text
    • http://wernitznigg.at/files/5853202464.pdfIn PDF document text
    • http://natalieshuff.com/uploads/file/fatosupogobebawakodado.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/dekufuxiwiw.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/merisajavamer.pdfIn PDF document text
    • https://arerp.kr/data/file///kosedizexivipobesixizawul.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/09/19/file/20210919_055500_131.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/64707884870.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/9fa1b1a564f429d4c85c1512db203276/gopirimesobawapetipaxa.pdfIn PDF document text
    • https://aristi-trap.com/upload/users/files/28762035559.pdfIn PDF document text
    • https://dpdpunjabi.myskoolapp.com/FCKeditor/FCKimgUpload/file/38018793682.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/75842582782.pdfIn PDF document text
    • http://zzzwchem.com/upload/files/73629418350.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_off0000bb72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB72 17012 bytes
SHA-256: 3e33ac71925c3819887f5b098886e541db695ac46b00ad7b4925dc6e70099a37
font_01_sfnt_off0000e78f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78F 10904 bytes
SHA-256: bbbbda5e1ae3f1afb0a43e3323651faf0d416f985ddca557b0ce43053bedf3ee
font_02_sfnt_off000100bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1