Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c14de3a8f027497…

MALICIOUS

PDF

79.0 KB Created: 2021-04-22 08:20:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 733486a8957038b9d9dedcc6d76b7a7a SHA-1: b64fb68f722f0f7bd93980bbec02e57658a40908 SHA-256: 7c14de3a8f02749759832adf8c889554154f43b2486164fc7d16688be0bbd578
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and a heuristic identified it as a link farm. ClamAV and an ML classifier flagged it as malicious, specifically as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an intent to redirect users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://aboss.by/sites/default/files/webform/12404161593.pdf In PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/bogobovimefegaf.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/35095474677.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/55418097166.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/zoxajetuvu.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/68406293253.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/bavowusakixonodokuja.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/78191676466.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=arris+tm822g+manualPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/42849177422.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/66931006591.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/46273532178.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/kozavexol.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/8342566550.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B4 5320 bytes
SHA-256: 706ca986af4424291f7864bd1fd17ed921ff8adafd164f1742b36d66a50ad609
font_01_sfnt_off000106b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B1 12524 bytes
SHA-256: 70c12ea40b5a21b31fc2d709d2cd1121e38cde3db32878297d46c260e23f362a