Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b55e58c4f83908c…

MALICIOUS

PDF

75.5 KB Created: 2021-09-10 12:44:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e42a5db0ab2f44cba7ea09067a24216a SHA-1: c1496f32e326a52da12593771210f5df17992438 SHA-256: 9b55e58c4f83908cb6b6d4da85cd57d224645043bbcc2735468e0a989acdf08e
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's used to distribute further malicious content or phish users. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing lures or malware droppers.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://infrive.ru/uplcv?utm_term=rate+of+change+calculator PDF link annotation
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/05eaffce4c50e39d3fd291fd3ea47e72/likunaf.pdfIn PDF document text
    • http://faurerom.com/userfiles/file/gepulasigejajuz.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/0c601ee31f64aeca739bbc45cf0b6417/zodusifabarofe.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/xuwilexataxunef.pdfIn PDF document text
    • http://belovosushi.ru/files/kaxozaxasuxigesirutof.pdfIn PDF document text
    • http://mezon.jp/userfiles/file/34319598528.pdfIn PDF document text
    • http://vangphutai.com/images/uploads/files/kufajoravibekiluneb.pdfIn PDF document text
    • http://cn-polylysine.com/d/files/53270823404.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613697fcaadcc---91781656914.pdfIn PDF document text
    • http://elvirajogsi.hu/ckfinder/userfiles/files/93791866956.pdfIn PDF document text
    • https://hamasataccessories.com/userfiles/files/fofetisipetune.pdfIn PDF document text
    • http://faizleathergloves.com/userfiles/files/60636275259.pdfIn PDF document text
    • http://kmjmt.com/news/upload/file/210907042106700629ios7g7.pdfIn PDF document text
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/lunaxijavedekox.pdfIn PDF document text
    • http://bolt.fo/public_html/userfiles/files/2410673863.pdfIn PDF document text
    • http://flirdining.com/uploads/files/75327133902.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/c3625011b80a4cfa860870ee24706a79/7784442752.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613a921d3185c---rilim.pdfIn PDF document text
    • https://rpaxis.net/userfiles/file/folokulusuxasedosokoz.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210907220825.pdfIn PDF document text
    • https://campfun.myhost888.com/upload/ckeditor/files/9468581806.pdfIn PDF document text
    • https://graphicart.ro/fckfiles/file/poputudegibilesexi.pdfIn PDF document text
    • http://louisiana-arts.org.s150269.gridserver.com/siteuploads/editorimg/file/50162966443.pdfIn PDF document text
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/fuxexarosarabolik.pdfIn PDF document text
    • 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_off0000c806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC806 10500 bytes
SHA-256: 6901d1ba32b2c9e9156c8bae6cb1b76d4afc08aaf8f41ccab7e70d68908d79e6
font_01_sfnt_off0000dfe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f7fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7FB 15900 bytes
SHA-256: d82829d5f69f522b57c5a38d73c66c98f39cba343c431da674a928faebcbec28