Malicious PDF — malware analysis report

Static analysis result for SHA-256 a811b136f72f5750…

MALICIOUS

PDF

74.3 KB Created: 2021-06-01 20:20:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 6f4ec0dc3e3b472edbc76b895177e70b SHA-1: eaf1be7ac7c7f105a36f9e32341d0c1f14879e36 SHA-256: a811b136f72f5750b34262fa70822c95e6404f990ed8e4fcd2cce377a19098ae
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 0.9996

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://nomylo.ru/pbw?utm_term=cobra+kai+season+3+review+reddit PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4367294/normal_60463fdd386d7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4419637/normal_604e203578c36.pdfIn PDF document text
    • https://falijufik.weebly.com/uploads/1/3/5/3/135349852/7ec02c64bf8bd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446259/normal_6056f59ebe2ac.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393632/normal_60153ac5306c1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408176/normal_606967b97bc19.pdfIn PDF document text
    • https://jojipizi.weebly.com/uploads/1/3/1/6/131606457/kiwerotelirukodep.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452377/normal_5fdde36160655.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413112/normal_5fe417d7e9d96.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495034/normal_5fc9d50157df4.pdfIn PDF document text
    • https://wejilosadala.weebly.com/uploads/1/3/0/8/130815097/7911815.pdfIn PDF document text
    • https://nimapefakapag.weebly.com/uploads/1/3/5/3/135324130/712a9.pdfIn PDF document text
    • https://laxonetamaj.weebly.com/uploads/1/3/4/0/134096763/260210.pdfIn PDF document text
    • https://vamekatowozi.weebly.com/uploads/1/3/0/8/130814347/8757628.pdfIn PDF document text
    • https://sowurudiz.weebly.com/uploads/1/3/1/4/131438308/daxepogubonite-vuzamigo-fizilew.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458150/normal_6046358915800.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://tisowowuduwe.pbworks.com/w/file/fetch/144427092/iobit_driver_booster_6.5_key.pdfIn PDF document text
    • http://xuvabufoj.pbworks.com/w/file/fetch/144456804/political_cartoon_analysis_the_gilded_age_worksheet_answers.pdfIn PDF document text
    • http://ruwezebom.pbworks.com/w/file/fetch/144427692/24602395801.pdfIn PDF document text
    • http://tosuvop.pbworks.com/w/file/fetch/144467397/woginisavenudijapobuxolan.pdfIn PDF document text
    • http://fubajulak.pbworks.com/w/file/fetch/144426147/temekaz.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CF 5116 bytes
SHA-256: 24c457caa6ead0d436a1b02a7d69db6b1e88cd34b3b5473035d67b8a50c613d8
font_01_sfnt_off0000eb50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB50 10108 bytes
SHA-256: 8657c66860e2222b62f6fb6de49df31c68c7a001e81ab73ecf2e0d05669eeb6c
font_02_sfnt_off00010def.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DEF 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71