Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b3e98c134238a43…

MALICIOUS

PDF

100.1 KB Created: 2020-11-19 01:04:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8e19a09961f45cf7259554e3f7a87caf SHA-1: 649b3258535abd738a28e50ab0956f4329cface9 SHA-256: 0b3e98c134238a4381a3edc31fb482492617d5230b11e4b0acc852c0f59110aa
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV and an ML classifier as malicious, specifically as a phishing trojan. It contains a large number of external links, many of which are likely part of an SEO farm or a link distribution network. The document body, though heavily obfuscated, suggests a lure related to 'managerial accounting answer key'. No scripts were extracted, but the presence of numerous external links indicates a potential for downloading further payloads or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://traffine.ru/123?utm_term=introduction+to+managerial+accounting+answer+key
    • https://cdn-cms.f-static.net/uploads/4379844/normal_5f9a95c2a9001.pdf
    • https://cdn-cms.f-static.net/uploads/4496013/normal_5fab754acc77b.pdf
    • https://cdn-cms.f-static.net/uploads/4368962/normal_5fa5ac9edd250.pdf
    • https://cdn-cms.f-static.net/uploads/4392439/normal_5fa209dc63afa.pdf
    • https://vufavinit.weebly.com/uploads/1/3/4/6/134649981/a342671188aae9.pdf
    • https://cdn-cms.f-static.net/uploads/4370284/normal_5f91325ce61eb.pdf
    • https://cdn-cms.f-static.net/uploads/4371023/normal_5f9191f63d7e6.pdf
    • https://xamonato.weebly.com/uploads/1/3/2/8/132814301/dawegazefomiji_korilozodev.pdf
    • https://lesofetu.weebly.com/uploads/1/3/1/3/131378838/lofakomirizufaf.pdf
    • https://cdn-cms.f-static.net/uploads/4365998/normal_5f87cc96d5b40.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/0530ca8e-0eb8-4b38-8a05-6f2fd5def973/rogue_guide_5e_dnd.pdf
    • https://uploads.strikinglycdn.com/files/b234fc2f-9bf3-47ca-b8ae-b10cbc4c4370/logitech_mx5000_manual.pdf
    • https://s3.amazonaws.com/nopomewegobij/zizexaseludanesipunu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014c0e.bin
42b07abcd5808a949f92a78a6e4012bdda23f3ec9058563c7b416543d6c32cfa
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C0E 5452 bytes
font_01_sfnt_off00015e99.bin
a344e5ccc6419763285a316bdaa000d20efdcc7beaa6fd5fe936aba24e3f533e
pdf-font-stream PDF embedded font (sfnt) at offset 0x15E99 10812 bytes