Malicious PDF — malware analysis report

Static analysis result for SHA-256 45b8b194d949b7bf…

MALICIOUS

PDF

87.1 KB Created: 2021-09-12 12:44:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: a7fd33b0b207e8ff3f8a058a567fb550 SHA-1: 7c90b0a55d0b1cb6c94525d6a978ba45cff13abd SHA-256: 45b8b194d949b7bfc048bbbc726aa8e55c37b975dea324edacd2c5dfc75059ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://synerhu.ru/uplcv?utm_term=windows+pdf+printer+download PDF link annotation
    • http://www.cottagegrad.ru/files/file/jajemabojalisipojejomugox.pdfIn PDF document text
    • http://thailaundry.com/imgUpload/files/mofebomilorigifojisided.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210908_AFCFE6D453C6BBDC.pdfIn PDF document text
    • https://ruta.hu/ckfinder/userfiles/files/77371675793.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/satukelemulodib.pdfIn PDF document text
    • https://alkalacarservice.com/public_html/userfiles/file/80457034678.pdfIn PDF document text
    • http://prtourusa.com/FileData/ckfinder/files/20210902_E80271E4BF883039.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/75741536770.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161365a245ff91---53997447149.pdfIn PDF document text
    • http://jia-longsofa.com/uploadpic/jialong151126/files/202109020116069483.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/46026016913.pdfIn PDF document text
    • http://araonline.hu/uploads/file/tusawofazesibodakijurofe.pdfIn PDF document text
    • https://ambalatender.com/upload/files/43823414963.pdfIn PDF document text
    • https://venus-forever.com/image/files/1094990567.pdfIn PDF document text
    • https://www.unicodesystems.com/wp-content/plugins/super-forms/uploads/php/files/8psejks25adjnv1e2djvsco116/sufagesazuwefopamu.pdfIn PDF document text
    • http://www.xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/texapufita.pdfIn PDF document text
    • http://khunghinhdepphuctin.com/media/ftp/file/kewate.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/moziwadupitomizoxinejuwek.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/ce3c28e6fe1ec090d744ecf00504713e/55388008575.pdfIn PDF document text
    • http://teenmag.cz/userfiles/file/77312546708.pdfIn PDF document text
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/namapemuxazejowajidaseb.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613743dc89e2b---saramevup.pdfIn PDF document text
    • http://mspchicagolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32540622077.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_off0000f120.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF120 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10932 17836 bytes
SHA-256: da79a0247ea6be02c077e07cf5931c66d9b4a0b5f590bb01785ad70ddf6ec8a3
font_02_sfnt_off000136e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136E9 10572 bytes
SHA-256: 1135ccc34ad4cd277bd2f2cb72d68f7cf34709c380f659a2c3dc73893e5396aa