Malicious PDF — malware analysis report

Static analysis result for SHA-256 c55a5eb896ee9fec…

MALICIOUS

PDF

114.7 KB Created: 2021-06-19 10:42:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: efee98cc023bd93b714d7d8057335106 SHA-1: 85a73600aea59f02886ed9da87634a4f52ac4e98 SHA-256: c55a5eb896ee9fec6a4a723164fe1e587394f42f838c1ae742bc5ae3d1e78628
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, contains references to 'Tekken 3 free play' and application metadata, which likely serves as a deceptive pretext to drive traffic to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b01df9071c5---kiwuletaluwulofemezek.pdf In PDF document text
    • http://imcborivali.org/userfiles/file/15778777584.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/emu6fo68ubi1sb85o6j3k95e56/37868384420.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beca17d3870---datozukomus.pdfIn PDF document text
    • http://win-sonic.com/kida2018/ck_imgs/files/74586449283.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160add9e2b74a0---merobekimusilevapov.pdfIn PDF document text
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/79554855516.pdfIn PDF document text
    • https://bienenaktuell.com/sites/bienenaktuell.com/files/file/xumapar.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a91cb2535---13616372458.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/toxorikodaj.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ee31289d0---resajejexa.pdfIn PDF document text
    • http://tumwebthailand.com/ckfinder/userfiles/files/36173494972.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16096328138d9f---86176406780.pdfIn PDF document text
    • http://rainbowcaterers.in/userfiles/file/59359574711.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160985e5e761fa---fimajazuvuzuzenuxaxamesek.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=tekken+3+free+playPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001868a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1868A 4996 bytes
SHA-256: 6721cb37970e41850691a317186bb9dee199bfbbc9766024a2f634e800e217ca
font_01_sfnt_off000197ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x197AC 11456 bytes
SHA-256: 7b30166501382c4187f2dff88ece0b224a3e4b73164cd4c118153cdcf093cf31