Malicious PDF — malware analysis report

Static analysis result for SHA-256 171bdb2101fbf881…

MALICIOUS

PDF

80.5 KB Created: 2021-06-14 16:07:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f7e31e0dbe180ca21074c04defa8e5c1 SHA-1: 0e40ae7f9ce71aea0462d67883fa256aa8ee24b1 SHA-256: 171bdb2101fbf881f989e93578570a08d8234796b774ad53b0e4dfc1da470714
156 Risk Score

Malware Insights

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

The PDF document contains numerous links to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ketchas.ru/uplcv?utm_term=4th+standard+addition+sums PDF link annotation
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d5303983f---wenikuto.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/fivulejigali.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f21731beb0---zedogomusuzirux.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160a1c690b7ca2---ruworudugutib.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f9cb02c733---vexobuwexat.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/93531129335.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/smndgcf3b6u0j97j5acne1qnm3/78937056618.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/98906011595.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/ueostjk3qvm5h4ihlastg52css/fagukevuvefufoza.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/b60f75d90ecb13e7670051894706fa80/jezuvafo.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab5bd2a1e8---66297052964.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c3bce3022c2---47066167539.pdfIn PDF document text
    • http://getem.eu/files/file/35715260979.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc41c88942---lulemorasoraxuvakot.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/51079762264.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000e850.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE850 5028 bytes
SHA-256: 8e135579005ff19b306546395d415eae8bf93b51b496182f707e455552bb4f87
font_01_sfnt_off0000f93b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93B 10808 bytes
SHA-256: f2f670afc14502a4e3a5ca49db62576675dd5a8936ade720f698e3dee448f473
font_02_sfnt_off00011e42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E42 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15