Malicious PDF — malware analysis report

Static analysis result for SHA-256 efbac215fc5c4e53…

MALICIOUS

PDF

81.6 KB Created: 2021-06-06 23:43:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 0d7e4f41db15d0695d933b11d1541187 SHA-1: a75eddd4bfe138ef8100ce1e644703c6f5e817cb SHA-256: efbac215fc5c4e53d79373ef03a29a3472e4e7fc53bb6b244b20403d9d204b46
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 0.9995

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://lozipotod.ru/123?utm_term=highest+common+factor+worksheet+hard PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4380867/normal_5fdb1a268c886.pdfIn PDF document text
    • https://gotagifegu.weebly.com/uploads/1/3/1/6/131607164/muxum.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491439/normal_6034078cbff58.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380223/normal_5fc888b33468f.pdfIn PDF document text
    • https://geredape.weebly.com/uploads/1/3/4/3/134349068/wivodegelixi_bilozal_tikavubopa_zukuf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484097/normal_605568b81b8ae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383475/normal_605be3339d126.pdfIn PDF document text
    • https://getazaxebu.weebly.com/uploads/1/3/4/8/134866961/duzazijopas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407664/normal_60b8980e46f9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471273/normal_60b82c153bb3b.pdfIn PDF document text
    • https://vakilelem.weebly.com/uploads/1/3/1/3/131379598/7353561.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450151/normal_60636fa65f35e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427095/normal_606807dc917db.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481068/normal_60071c67ead70.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391001/normal_600db235f091f.pdfIn PDF document text
    • https://gupoxebexu.weebly.com/uploads/1/3/4/3/134337811/6695a21a8cb0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481520/normal_5fcfed36e497b.pdfIn PDF document text
    • https://xifisipur.weebly.com/uploads/1/3/1/0/131069870/adcb605.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479214/normal_604d1017037d2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367617/normal_604d2beb11de6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472774/normal_604ae4d68f09c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467318/normal_6050de0336f48.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE0 5520 bytes
SHA-256: 7b577198ec5e518c3893ae2052ad8f3e5e315e4add39a441080c2ba89da75654
font_01_sfnt_off0000fd8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8D 11028 bytes
SHA-256: 3c88a81779739ec14afdfddbec52e20eab16dfc11acc0ebd87cd3f0168ae1863
font_02_sfnt_off00012340.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12340 16204 bytes
SHA-256: e93acd332f5893643511f4cefd38969ad5c744ad1b08842a788b6be7d277dd15