Malicious PDF — malware analysis report

Static analysis result for SHA-256 b16a879f9822a6e8…

MALICIOUS

PDF

82.8 KB Created: 2021-09-19 18:14:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1314bbd447ae956dca8cf0698a03a3ad SHA-1: 4acec73e3c562b47064a7174390599d965ea2153 SHA-256: b16a879f9822a6e8d3bfdfaa85cc0f23ae257d2bf72ec9f3f8f57afb49757c69
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or downloader attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://krainaogrodow.eu/zdjecia/fck/file/97836091784.pdf In PDF document text
    • http://elitaliaweb.it/upload/file/92557524387.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/52559658133.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/125f6c8bc35eb233f45ef598ec564853/pirenazetupubujedena.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/39054953425.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/161407bc05c456---12078042306.pdfIn PDF document text
    • https://kokomanis.com/contents/files/96765904185.pdfIn PDF document text
    • http://youngthisyear.com/ckfinder/userfiles/files/tadabuvopirobikubutoguxiz.pdfIn PDF document text
    • https://edenestates.com/ckfinder/userfiles/files/20804031572.pdfIn PDF document text
    • https://basealimentare.it/webroot/files/fck_uploads/File/31591234813.pdfIn PDF document text
    • https://norservis.com/files/files/duromedovutotosowabal.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/42141123279.pdfIn PDF document text
    • http://craj-ops.craj.cz/soubory/pojugobegim.pdfIn PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/ninofidi.pdfIn PDF document text
    • http://agrocare.hu/ckfinder/userfiles/files/sipabovowixodakegetujita.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/lubowarujiban.pdfIn PDF document text
    • http://140.121.180.103/ckfinder/userfiles/files/71453341923.pdfPDF link annotation
    • http://puisan.ru/uploads/file/kasigofubo.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfa5fdc700---marukodudofikaribuxupemi.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16138a0bf6b902---ponuxududizileze.pdfIn PDF document text
    • https://h1t-url12shio-turbo.com/contents/files/3215255558.pdfIn PDF document text
    • https://jurvamartin.com/userfiles/file/pidapaxewuxebunufedubiko.pdfIn PDF document text
    • https://giltmorestukko.hu/ckfinder/userfiles/files/35231092854.pdfIn PDF document text
    • http://fuhua.tumujike.com/assets/upload/files/202109042103041767.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=textfree+plus+apkPDF 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_off0000dea4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6BB 10292 bytes
SHA-256: 94d2b5d04957e731d80c5ac3ade452d4d82dcde6beee750f69ee5df8069d22eb
font_02_sfnt_off00010e1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1E 18368 bytes
SHA-256: e744e58374f1d7807ae831ef6871ef754bd744ea10c13d3885791c2037f6b682