Malicious PDF — malware analysis report

Static analysis result for SHA-256 89b408bbf62d6943…

MALICIOUS

PDF

82.6 KB Created: 2021-06-13 18:01:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 64cb12be363da1a8287dafba9e047f8c SHA-1: b6c3d3e600e339cebc6de30a85b4197bd0d90a2f SHA-256: 89b408bbf62d69431e80a8ca4a8c61c36bc22a906a455cf5881ef0f6cad146c2
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing lure. The document body, though heavily obfuscated, appears to be a deceptive lure related to academic materials, aiming to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://krisoc.ru/uplcv?utm_term=principles+of+macroeconomics+by+hl+ahuja+pdf PDF link annotation
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/34a2544afca6c57964291ea1091811c9/sofesipagurutuxewemu.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/sm4ct7cv2hqb2p6gbc5otj2i01/65374183419.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b36d8286b92---79721044005.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/3a779e4dfb7eb0a6dba0b8dd234aecdf/jumateb.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/85904740996.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077988c8153d---84065395344.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8aac0a1144c09d561e7dee6cefee85d8/10704593494.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/i21dpn557dj7ljbddb2kaonj63/83205832723.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b09826b26e5---lixekesamaxexu.pdfIn PDF document text
    • http://atut-biuro.com/uploaded/file/88664670049.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/rekodoxokisujo.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/fa8180bac67e8a3c26311c8b4535be0a/43704342573.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160aaeb57e841e---xesodataxerenekirobofoka.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE429 5712 bytes
SHA-256: fb100458aec0da91a644aa5ee150d83f967dd035e2450b962d6c2b347c30b08a
font_01_sfnt_off0000f76a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF76A 2268 bytes
SHA-256: 72a3fe65f0a21df30f240897224061cfa351088b80a4eb601fb5defb198ec993
font_02_sfnt_off0001017c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1017C 10864 bytes
SHA-256: d5436887903320f991871412d10a1c7f48c81b4f6000b988763c9e9b2103c037
font_03_sfnt_off000126b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126B8 16220 bytes
SHA-256: baf231d2b9e9e90fbb2dedac8720218800ad083355f0d0af241188a8d45664d8