Malicious PDF — malware analysis report

Static analysis result for SHA-256 1374759526449731…

MALICIOUS

PDF

152.3 KB Created: 2021-08-14 14:15:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 668ba693ae3057e45d310233daf04cce SHA-1: 998f048f9bf315a0874fcb3f37927931be34cebf SHA-256: 13747595264497317d165205306dd3a3f380591c514d298a57b0d4276e5d96c8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the overall structure and URL distribution indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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://cructi.ru/uplcv?utm_term=beer+brewing+process+flow+chart+pdf PDF link annotation
    • http://x04ydivan.ru/userfiles/file/dubopiparaxid.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/8433181a094e27a0a2ab6d2fcb1229da/50517472850.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/59903701396.pdfIn PDF document text
    • https://livresdarts.com/ckfinder/userfiles/files/11654386265.pdfIn PDF document text
    • http://cymrozgreatdanes.com/clients/1/1a/1a407d8ccac5525c71aaafb6b4664123/File/6415034191.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/jozagidovomeguvu.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/jidibegonurigimogidof.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/13250493963.pdfIn PDF document text
    • http://bilmatbasim.com/userfiles/file/dawulepogexub.pdfIn PDF document text
    • http://dharmapremipariwar.org/userfiles/file/fuwajiledovofe.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/wemigaw.pdfIn PDF document text
    • http://sculecuacumulator.ro/app/webroot/files/userfiles/files/16083032013.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/1lsja9lnk1k368solfb4dbml80/37785290748.pdfIn PDF document text
    • http://novichiha.ru/pic/file/95579525317.pdfIn PDF document text
    • https://capitalsyndic.com/userfiles/file/gofoluwonimikija.pdfIn PDF document text
    • https://kompaspt2.com/contents//files/rugasaxiresimizur.pdfIn PDF document text
    • http://normel.org/files/upload/file/57897624447.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161084621db632---37366982195.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093e6c9ca0a1---29078613152.pdfIn PDF document text
    • http://hulstcustoms.ru/uploads/files/50401350303.pdfIn PDF document text
    • https://maria-galland.ru/files/file/kexebenogiritoxap.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/9d7313bd1e27a78ead9ee93b7a301a8b/nixebuzuvudimigaxesa.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/gijalovoripanarix.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f829bc36a---nosamezuja.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_off0001ed77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1ED77 19728 bytes
SHA-256: ed5dcbf1f4ddca742f7f2d71f70a0dc8a22de8c9805cafa8d26b89c5d9d4786e
font_01_sfnt_off000220aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x220AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000238c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x238C1 11180 bytes
SHA-256: 3cf8f74c0376291c0226d115e8bd347aec878ad709d76640b184a6110537f8b2