Malicious PDF — malware analysis report

Static analysis result for SHA-256 28bd6373e47196a0…

MALICIOUS

PDF

72.3 KB Created: 2021-09-11 21:22:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2ca22ba2417cd8fe9ece91d5b8985396 SHA-1: 20c9207cb91307a2f202ba48f37faa21f6c9f65a SHA-256: 28bd6373e47196a0385dfb77086325c11c2d71a3078f96cc3316e3d55c2c05d5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to domains that appear to be hosting PDF files, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically identifies this pattern, indicating the document's purpose is to drive traffic to external sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ranch.pl/files/file/47566700191.pdf In PDF document text
    • https://yifff.se/userfiles/file/12363995274.pdfIn PDF document text
    • http://pogologistics.com/ckfinder/userfiles/files/bipakowimuwefikofob.pdfIn PDF document text
    • http://montoaneli.com/ckfinder/files/20738705134.pdfIn PDF document text
    • http://sarkanyhajo.hu/files/file/vitoxevulex.pdfIn PDF document text
    • https://makenie.com/upload/files/bezejijil.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/46026016913.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/popefuwubegenemaxivo.pdfIn PDF document text
    • http://divapharma.com/uploaded/file/90753333595.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/97300222323.pdfIn PDF document text
    • https://akrmedia.no/ckfinder/userfiles/files/15697096385.pdfIn PDF document text
    • https://designmaster.in/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/jojepitimorelajinigeduno.pdfIn PDF document text
    • http://workontext.ru/media/file/81255557751.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f260cc3232---41005697548.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/69426080030.pdfIn PDF document text
    • http://kmjmt.com/news/upload/file/210911040140545328v1w5g6.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202109/file/1630770704.pdfIn PDF document text
    • http://chiesamadremarsala.eu/userfiles/files/39352525373.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/zetujujepevubozelofurefi.pdfIn PDF document text
    • https://telenovella-bg.com/files/6475252199.pdfIn PDF document text
    • http://okzawidow.pl/img/upload/files/9855797226.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/7ad66f9e9acb49c441c9415f3ca3046f/kedupewiwasivusi.pdfIn PDF document text
    • https://abicecream.ru/ckfinder/userfiles/files/48312675962.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/494345603.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=best+gas+prices+near+mePDF 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_off0000b89c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB89C 16720 bytes
SHA-256: d8f35ebeacffa59cc3c2ec2725772b8570c6cbe58b549139a29df3a7f95ca627
font_01_sfnt_off0000e3b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fbca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBCA 10604 bytes
SHA-256: a5d034382a7dfb3fa9b9d8119819d3aaba43ff46721ee5829e1304c4adaf53f6