Malicious PDF — malware analysis report

Static analysis result for SHA-256 133bbc26fc0b6acf…

MALICIOUS

PDF

84.0 KB Created: 2021-07-02 20:03:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 2492b52a2b664551ae904fc26418f779 SHA-1: 96bc8b51fedce174795538346f7000b53d592f13 SHA-256: 133bbc26fc0b6acf80a9a10d2b88478f1e8369e5ff3df6017d8f9f6785fe4afd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous external URLs, some hosted on compromised CMS uploads and disposable domains. While no scripts were explicitly extracted, the PDF format can embed JavaScript, and the overall structure suggests an attempt to redirect users to potentially malicious sites, aligning with phishing or SEO spam tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://stoewebdesign.no/userfiles/file/polijubaluk.pdf In PDF document text
    • http://www.bash.cl/media/file/87883826621.pdfIn PDF document text
    • https://pensiunea-escape.ro/ckfinder/userfiles/files/61921392505.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/75illgpk8m54hl58aag65svvrn/54143651576.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16094bdcaa9d90---83569862285.pdfIn PDF document text
    • https://www.surajinformatics.com/wp-content/plugins/super-forms/uploads/php/files/a52f0a9c6be654d770ba5063d6da636b/2538950799.pdfIn PDF document text
    • http://phanbonvbm.com/upload/files/72267514462.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e8dccba5fd---duxojawoxogi.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5eb4bba5ba---27691701792.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/73498133164.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3d07a32e3---8868450618.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088291499b07---8944595621.pdfIn PDF document text
    • http://chinahongji.com/d/files/nelusuva.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bce488c2d72---volasudureguturotuxi.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa1969f708---duxeniguvite.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/ruxakinaponobini.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/bfe65e219fa4bed2bc9272b79dff38c8/11337557230.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/5e24d30f472847fba5e1d8b92f4ad20d/tegawugugowodewiro.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/vanuxiju.pdfIn PDF document text
    • https://myveolife.com/wp-content/plugins/super-forms/uploads/php/files/7489ddf21689819da8d2c1a1ffd2bde0/sevufis.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9bd47165be---jotamivagumenu.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/82712945868.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/86e248d534456b723cdbbf7ca1183b7e/vulafipukiko.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081cf26226f5---samukapuzekowi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=conversion+factor+between+cm2+and+m2PDF link annotation
    • 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_off0000df1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF731 11032 bytes
SHA-256: f510f75cb8b9b622cc01c624540fff0c83a7d9b958b8499773554960d4020774
font_02_sfnt_off0001110c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1110C 18016 bytes
SHA-256: d721ae1b10bbe99da99ed64a2631cb6deb049f2a3c18fc7616ac2e02988d5cd6