Malicious PDF — malware analysis report

Static analysis result for SHA-256 1041b4c36b803996…

MALICIOUS

PDF

71.2 KB Created: 2021-09-20 12:07:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 3285900869b98eb69b47c3e2ff6b62d7 SHA-1: c2cc83b4b51309e02bcce020d4cdf323db9cafcc SHA-256: 1041b4c36b8039966f06bc8be7590e757fa6f3e74c8be840cc1e7cc3e428320e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on potentially compromised CMS uploads. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://neurooperations.com/ckfinder/userfiles/files/2990147110.pdf In PDF document text
    • http://odpadykj.cz/UserFiles/File/bademesulunojuwibiveziwi.pdfIn PDF document text
    • https://strongpointmarketing.net/userfiles/file/5743904785.pdfIn PDF document text
    • http://otohyundaidanang.com/uploads/image/files/85641507682.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/7m1pd3jl1g1usm7j2j35bo5kv3/42126932345.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613dceeb91c52---40521899885.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/b0c4b5251fb1171da396ce0ccf68c659/wixuvepajutejelatib.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/xudajutiwa.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210916_032607.pdfIn PDF document text
    • http://gizmakina.com/depo/sayfaresim/file/18994010523.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/29236316178.pdfIn PDF document text
    • https://keongracun.org/contents/files/18793628200.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/revadod.pdfIn PDF document text
    • http://ylgems.com/file_media/file_image/file/fixefajixefow.pdfIn PDF document text
    • http://www.sospapa24.com/lib/ckfinder/imgupload/files/masefuxamez.pdfIn PDF document text
    • http://hyundaihungthinh.com/uploads/images/files/tofegu.pdfIn PDF document text
    • https://bunianco.com/other_files/File/65253477363.pdfIn PDF document text
    • http://ronaldtan.nl/images/photo/27788144604.pdfIn PDF document text
    • http://hadt.vn/upload/files/lawopojozoxapanunewu.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613059e327284---60794890427.pdfIn PDF document text
    • http://familiegravesen.dk/ckfinder/userfiles/files/26558022744.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/54826553768.pdfIn PDF document text
    • https://gabconstruction.com/ckfinder/userfiles/files/41510546441.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135680d627a5---zomupugo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=fall+guys+android+appPDF 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_off0000b783.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB783 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF9A 10528 bytes
SHA-256: 17644e1acf86f19f000a162046992ef509a7a912f82f68cc3f07c0d21438a12a
font_02_sfnt_off0000e76a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76A 15608 bytes
SHA-256: 51f3813d7831f709f209593c13bf7ada24a4db38d6612a516c613c12207fe17c