Malicious PDF — malware analysis report

Static analysis result for SHA-256 73d5a7281be4a7a3…

MALICIOUS

PDF

79.4 KB Created: 2021-04-19 12:33:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 779ea491e455c8e966719863ab5a442a SHA-1: 53ff967c21b1d2f08982de4f0f26aa972ef5610c SHA-256: 73d5a7281be4a7a33acb242da83e3e89174aaf6534a2ebb2d549a0083b37dced
246 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a callback-phone (TOAD) lure and a password-protected-archive lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://zajinet.ru/strik?utm_term=triton+atm+customer+service+number PDF link annotation
    • https://zijananuwale.weebly.com/uploads/1/3/4/4/134438714/jilunep-disijufowab-sanaxitajinakim.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409997/normal_605da347234ec.pdfIn PDF document text
    • https://rugozodamutar.weebly.com/uploads/1/3/4/6/134600103/taxaxatalufina.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4390051/normal_6007c06d3f3fc.pdfIn PDF document text
    • https://ziriponu.weebly.com/uploads/1/3/2/6/132696112/6851128.pdfIn PDF document text
    • https://dojulukasinu.weebly.com/uploads/1/3/0/7/130776790/5139150.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369907/normal_60367cafdc50b.pdfIn PDF document text
    • https://pimalikatirowo.weebly.com/uploads/1/3/4/0/134040386/veketore_dixis_gupijuw_sabux.pdfIn PDF document text
    • https://ratofesut.weebly.com/uploads/1/3/5/3/135304008/tujejam.pdfIn PDF document text
    • http://reduslim-shopofficial.site/decision_tree_pruning_python_exampleqpysc.pdfIn PDF document text
    • https://wejolizamu.weebly.com/uploads/1/3/4/7/134766198/8529315.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445737/normal_6021f1db845bb.pdfIn PDF document text
    • http://shopsmmv.site/hallmark_the_night_before_christmas_pop-up_book_with_light_sounddtgeq.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://299bc67c-4c9a-44ea-852c-18f2d39dca40.filesusr.com/ugd/954c8b_27cf185678744b8799b16a41911a6166.pdf?index=trueIn PDF document text
    • https://43a2ba88-5de9-465b-b95f-6a4d82f2d06e.filesusr.com/ugd/dcbeda_0315fbfb602f4fc68dae5604cd77b90a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tizowodifi/94490980418.pdfIn PDF document text
    • https://s3.amazonaws.com/kugelilizibuwum/32406469045.pdfIn PDF document text
    • https://s3.amazonaws.com/tetenifeme/ginajonofulupibesiroruv.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_off0000f81e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF81E 5060 bytes
SHA-256: d8b0225e042236d9d8c8184be17ed43a9b1a37aec186160ef4657a240f91f9d3
font_01_sfnt_off00010940.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10940 11420 bytes
SHA-256: 76a371f75a62830748f05cc1b6a1fb4bf5cbe5a463a66f19437024f044182847