Malicious PDF — malware analysis report

Static analysis result for SHA-256 833ccf1009d3d5fa…

MALICIOUS

PDF

81.6 KB Created: 2021-09-15 15:49:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14d78a7a64c78324163f547712f03df1 SHA-1: b1e038ca8c6a49f8dd533f38367ff31747d819ab SHA-256: 833ccf1009d3d5fa1ece68e578c80f39ceb1ccaff707d9cba6867e27c518b9b2
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised websites or are part of link farms, suggesting a phishing or malware distribution scheme. The document body is unreadable binary data, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://valeaflorilor.ro/img/uploads/file/kaweziwewalokap.pdf
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/54319078302.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/161382147daeb2---dinemoj.pdf
    • http://pvvc.cz/files/71655288945.pdf
    • https://cleaner.pl/userfiles/file/pepovika.pdf
    • https://projekt-lesen.de/userfiles/file/jovulazelelijipime.pdf
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210905_180051.pdf
    • https://acrgruppe.de/userfiles/file/77529410761.pdf
    • http://fjzy18.com/image/uload/files/netamazudofigesuxoka.pdf
    • https://vinamex.info/uploads/news_file/39791762340.pdf
    • http://ukrainski-rosyjski.pl/userfiles/file/32468608515.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138601c1e476---xelotaxolulaje.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebb64b890b---goridapamonofumirid.pdf
    • https://amoslodge10.org/ckfinder/userfiles/files/janoluwizapesami.pdf
    • https://h1t-url12shio-turbo.com/contents/files/48308307399.pdf
    • http://cascinamana.it/userfiles/file/xenifevejezidukixifipodu.pdf
    • http://hyunsin.net/userfiles/file/suxadiwagezipixe.pdf
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/59ff82c4936f05417179744d1e0b84e1/42413546482.pdf
    • https://congnghiepxd204.vn/upload/files/99112800893.pdf
    • http://reclameindex.nl/images/uploads/67865012597.pdf
    • http://www.jobsincrete.gr/images/_user_na/file/kafikimasexiwoluk.pdf
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/tusofofuravutijuzepiforad.pdf
    • https://marblobaths.ph/app/webroot/img/files/25214672941.pdf
    • https://chungcungoaigiao.vnpec.xyz/uploads/files/lomedu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=vidmate+old+version+mod+apk
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d996.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD996 16792 bytes
font_01_sfnt_off0000f1a8.bin
d60051716caa2623e241e524bcdec73d923a9aaf4279bde36d25fe5932fd9a76
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1A8 17912 bytes
font_02_sfnt_off0001201a.bin
4561f00b082f44fb263076cc59e9405736027a9b745e4925e10bb61b0e4a7426
pdf-font-stream PDF embedded font (sfnt) at offset 0x1201A 10680 bytes