Malicious PDF — malware analysis report

Static analysis result for SHA-256 b37a025e995a0c51…

MALICIOUS

PDF

83.7 KB Created: 2021-07-06 22:24:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 76ab343d2ae4f7bbb882bd520a6e3287 SHA-1: 0d4a73bc98fc54d0b3657bb1d6bd9975eb5edd3e SHA-256: b37a025e995a0c516c40bb70f746aa4e3e389a67af9c51c36a60e8692229fc3e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution by redirecting users through these links. The presence of embedded JavaScript (T1059.007) further supports its role as a malicious document, potentially used as a spearphishing attachment (T1566.001).

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://classiccar-jp.com/js/upload/files/6990166028.pdf In PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160e4446dbff9a---84825596669.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/10b0cde21f668ba6792f2742b3a17ece/86973277625.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/45837236297.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a546b66598---xipejizujemesez.pdfIn PDF document text
    • http://markone-tools.com/upload/files/69891487835.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/weduxumuxotovarez.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/zonavufenufufokok.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/0eoe3upq7gm3ou0mhjv9vbd8g2/luninomanu.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b0cea2e6f4e---fovesuze.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/f2nbhec4ekret8c5t1n8e00aig/donutabatudevixeleg.pdfIn PDF document text
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dad12400af0---64155007169.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/16080ba2f616a2---46734382457.pdfIn PDF document text
    • http://landia-print.com/pdir/file/kidanosuj.pdfIn PDF document text
    • https://aokman-drive.com/d/files/deken.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0df53a8b1---84062000378.pdfIn PDF document text
    • https://pelletier-tp.fr/ckfinder/userfiles/files/4688037802.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2c6e25b50---gapojegipozit.pdfIn PDF document text
    • http://syarmarka.ru/userfiles/files/16213811686.pdfIn PDF document text
    • https://associazionedynamica.it/uploads/file/58578882264.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=chronic+bronchitis+treatment+at+homePDF 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_off0000e60e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE60E 10620 bytes
SHA-256: 5b6efe689d842985c3214bee08d847200d881892814bb1a7c9762b3e57f1ee3f
font_01_sfnt_off0000fe2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001163e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1163E 16824 bytes
SHA-256: 0c28ae738794612708de5722f2f98ca9b11e18f0a1abd094cc80d5b5a905ac8d