Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1651f385b242446…

MALICIOUS

PDF

75.1 KB Created: 2021-06-04 07:12:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 5f969a657b1bab1d0bfe95ad826324b4 SHA-1: ee54c7e132a1555ecf3c0829c3680d39d0a4d02a SHA-256: a1651f385b2424469b6e3ba4849626ae1d3eecbeb3480ec2cec89e7f281950bb
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9991

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
  • 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.
  • 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://medvor.ru/pbw?utm_term=important+c+programs+pdf+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481052/normal_602a4793552f4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411228/normal_6054558c21e8f.pdfIn PDF document text
    • https://rapexinet.weebly.com/uploads/1/3/4/3/134328854/d618682e33691.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4499972/normal_60065b69470a6.pdfIn PDF document text
    • https://moremutinujiti.weebly.com/uploads/1/3/4/8/134865562/xanogugixufovoxa.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4416930/normal_60b674d831641.pdfIn PDF document text
    • https://menelaxewo.weebly.com/uploads/1/3/4/3/134362368/7e235.pdfIn PDF document text
    • https://lefatelaxebaj.weebly.com/uploads/1/3/5/3/135398996/a9f0f26.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4478923/normal_6009a0604c651.pdfIn PDF document text
    • https://burekanokem.weebly.com/uploads/1/3/1/0/131069897/3652676.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4369671/normal_60b6010cdaae9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474989/normal_604ff310ae5f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480393/normal_601d0cb88be02.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4529149/normal_5fd9d604f35cb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463552/normal_5fe6d6f010bec.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383314/normal_5ff66a0e5ec90.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4487197/normal_600047883cf25.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446015/normal_5fdb02f301f6d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/77f5ebe7-71b4-41ba-8509-9ecfd74649d5/garab.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dcd3aee5-6c44-4391-9c5f-f91b1d01e007/where_does_the_flower_of_life_come_from.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/57a10fc7-0a49-4e9a-8e96-e163ba84ff64/12638327458.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ba73504-6cd9-44ef-ba6e-a7600ed12097/tp-link_300mbps_wireless_range_extender_starter_kit_tl-wpa4220kit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/386332e1-cbea-48af-9d29-068f3cbe9beb/58655247660.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c1f0c10b-0fea-4f92-9a33-184709776535/rojepagolajezix.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_off0000e712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE712 5504 bytes
SHA-256: 1889c4578b900a34a6c0af514ddd16411e662017c9c27fbf00f7b7a459555db5
font_01_sfnt_off0000f9c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C5 10716 bytes
SHA-256: b02f7e820bc0b6fd8bd6b1c00e6d4c11b63f16de9d8b56e129931fe9f21b6ac9