Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea1fffb57492a49c…

MALICIOUS

PDF

82.1 KB Created: 2021-10-08 03:47:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 68ba39ab43a84306af6f6b87a94f7aad SHA-1: 04bb5d0964d95c7e43878dcec1c3f1f254c7ac58 SHA-256: ea1fffb57492a49c6bb578fa9cb9e1d752553dc21c7818a5a1b17a810070f0e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress upload directories and other disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/0aa3bd77c54508557fa6714d4407b151/94502946434.pdf In PDF document text
    • http://staresecurity.com/userfiles/file/49467642295.pdfIn PDF document text
    • http://stelmart.ru/userfiles/file/mosizilupovunofinutagar.pdfIn PDF document text
    • http://qhchemicalsfeed.com/upload/files/48785444251.pdfIn PDF document text
    • https://websbag.com/uploads/files/befokakasok.pdfIn PDF document text
    • http://bsa-billiard.by/images_from_html_editor/file/voliwevatuza.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/gesitulumes.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/53161464498.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161307f0f105e3---damobileba.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613284bc2d721---mopumosala.pdfIn PDF document text
    • http://aristosaigonhotel.com/uploads/files/6125856468.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/sulitefoporavinelunaf.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/kidefavidelomikibebivil.pdfIn PDF document text
    • https://arerp.kr/data/file///38467005578.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/9991a24f35c00a8e1902ab2b25e83c54/3328033476.pdfIn PDF document text
    • https://7mark3t2-7aya.com/contents/files/44506286450.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/80867927212.pdfIn PDF document text
    • http://catherine-massage.com/ckfinder/userfiles/files/19478544.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/23525009333.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/pituromalipanobuberoza.pdfIn PDF document text
    • http://imbirimbir.ru/files/xanevewoposazulumadotow.pdfIn PDF document text
    • http://cftckr.marketsearching.com/upload/files/90301520565.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/753294647ca638d43a80fb0d405838ae/zidedopitunuxor.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/3012223678.pdfIn PDF document text
    • https://rubenferro.com/userfiles/file/wetoxanabaxejigataxowalul.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+save+some+pages+of+pdfPDF 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_off0000d8f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF109 18792 bytes
SHA-256: cacab94506f29cf414b63be591fe740d78cd08c957131108d407bf17767248a8
font_02_sfnt_off00012293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12293 10640 bytes
SHA-256: d8fc4e866b2c77cd534d282c77e2e2ff353d586982b5be54974199ceeaaa1358