Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec8c350a7f0d3045…

MALICIOUS

PDF

85.6 KB Created: 2021-06-30 05:07:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f7e70e34ba27bddea9af6d2094c4af71 SHA-1: 4682614b9f8139d0d468287d8a46e703efbc1b38 SHA-256: ec8c350a7f0d3045f2b28fd8ff9302d7655a5aa7be44f45f5cf23d1d8116bb4b
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 critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The document contains numerous external URIs and link farm patterns, suggesting an intent to redirect users to potentially harmful websites. The presence of compromised CMS upload links further supports this, indicating a pattern of using vulnerable web infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://wastran.ru/uplcv?utm_term=lesson+14+graphing+factored+polynomials+answers
    • https://alakharia.com/public_html/userfiles/file/78655787581.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/d554da45c403b0755a9594466c299196/sogamejupadodavitemuko.pdf
    • http://quickvideo.nl/userfiles/file/vuretu.pdf
    • https://aartipalette.com/userfiles/file/22139114392.pdf
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160829d759090f---41208619450.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/p60oqv806a6ugg9hsshdcalgn7/vufubalikobapu.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608300b1785bc---muzorikulaxa.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/vmd1o63olc63jhejdtgcfvai14/30805733660.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/2f64dc078ef2d2ab3ee487927f29cea1/50885572552.pdf
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f4fdaf3d8f---40686532835.pdf
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/a15cafaec767cee2402ee325124d3610/piluzagazura.pdf
    • http://cl-pub.com/files/files/15052339960.pdf
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/isn5ld6fap93g639ffhdvv8rcu/92387363933.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609fc336e80aa---64582445976.pdf
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/9c312d21fd4647768161f8464112d877/20065432507.pdf
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/di0l8l5og247kv7upr7ki21oht/zipugemuwozezir.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/odjpgrgbq5uuk1060eiivvggsh/vikupugokulosa.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606defd2aaaec---14431486972.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae4987d904---58490957003.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/5nj9g2usl68np2grc6n6r27uk8/78170443792.pdf
    • http://cuatudongsaigon.vn/uploads/files/35337714996.pdf
    • https://mobilieroccasion.fr/uploads/file/88051246858.pdf
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c368dd31548---31553575466.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a2f03c2d3bc---92382302917.pdf
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/fb7f9459235e2632efc0b2707227cee1/junajikibowijiz.pdf
    • 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_off0000e5fc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5FC 16792 bytes
font_01_sfnt_off0000fe13.bin
f39109c758ade9c91c9f8f61cf4c69c5b15905ee6db6cdcdc39d4db1cebf2b07
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE13 11352 bytes
font_02_sfnt_off0001188e.bin
fac2c3c7fdd13207d8b3a369149edf47ceef2bd8761ae521f5384bc83e526a78
pdf-font-stream PDF embedded font (sfnt) at offset 0x1188E 18668 bytes