Malicious PDF — malware analysis report

Static analysis result for SHA-256 56da596e978a7a3c…

MALICIOUS

PDF

80.7 KB Created: 2021-09-18 08:16:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5d65367af89efbe636f70d484028447b SHA-1: dd2696e74220ffddce7416b5bf7f642f3ef2a237 SHA-256: 56da596e978a7a3c57220d372fceb966fe26907530ced626b443aa968e26ef88
126 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. It contains numerous embedded URLs pointing to various PDF files hosted on different domains, indicating a link farm or distribution network. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the document is designed to manipulate search engine results or redirect users to potentially harmful content. No scripts were extracted, but the overall structure points to a phishing or content distribution attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://stmarysharipad.com/userfiles/file/ferixurasusekemura.pdf In PDF document text
    • http://huijingweb.com/upload_fck/file/2021-9-16/20210916100827513231.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/28629942127.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/19495011970.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/66131020932.pdfIn PDF document text
    • https://somogyplusz.hu/files/48637219067.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/batidajonolorewovebun.pdfIn PDF document text
    • http://www.coverseg.com/uploads/ckfinder/files/11757178452.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143a23a83fc9---12214796440.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/37270371983.pdfIn PDF document text
    • http://isvpro.com/custom/files/kowilesodizafanuj.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109050205351462.pdfIn PDF document text
    • https://cafesca.mx/ckfinder/userfiles/files/fulipujekurobupatize.pdfIn PDF document text
    • https://lexconsulting.ro/webroot/files/media/99811313643.pdfIn PDF document text
    • http://royalwedding.jp/images/blog/file/70500448973.pdfIn PDF document text
    • http://palestraarkadia.it/userfiles/files/54803363565.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/gaxidanolusi.pdfIn PDF document text
    • https://protraderin.com/userfiles/file/rakadobod.pdfIn PDF document text
    • http://decaldankinh.net/upload/files/duzituposirulafudoroguv.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/59683576066.pdfIn PDF document text
    • http://graviroz.hu/ckfinder/userfiles/files/sapopo.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161402cd0033f4---jekipivotixarewepikejuwiw.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/tumux.pdfIn PDF document text
    • http://maychebiengoduykhuong.com/media/ftp/file/xoxiguriwepaledoketemude.pdfIn PDF document text
    • https://venus-forever.com/image/files/33558039309.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=free+rpg+for+androidPDF 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_off0000d857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD857 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f069.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF069 17604 bytes
SHA-256: f31839aa0eacb849a4d8d863a8855728a7a987f5742d5acdc69478a1c9e61258
font_02_sfnt_off00011e4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4C 10336 bytes
SHA-256: 769cc511a0df02bfa978e6b16281e54baf4f65f8c11cf82b8cb4d34413ec1957