Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b9f03b46247d8a…

MALICIOUS

PDF

76.1 KB Created: 2021-11-10 18:56:21 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 1cf8205a547ce534dcc2f2838dbc43c3 SHA-1: 79d12047ecc482c3d8ce48d7731ebff2afea5e70 SHA-256: 31b9f03b46247d8aae227955f3f1c50156fc545b39714f11d4683d362e2a17cf
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pistant.ru/uplcv?utm_term=learn+shell+scripting+step+by+step PDF link annotation
    • https://littleedupark.com/ckfinder/userfiles/files/todelabesonoxaxa.pdfIn PDF document text
    • http://giaexploring.it/userfiles/files/tugapunumo.pdfIn PDF document text
    • http://budaikepkeret.hu/uploads/file/13254977402.pdfIn PDF document text
    • http://caminodesantiagoenmoto.com/assets/ckfinder/core/connector/php/uploads/files/supuwukej.pdfIn PDF document text
    • http://ogcdc.org/uploads/ck_upload/files/kowuvujazinukesa.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/37476031277.pdfIn PDF document text
    • http://esllearningbydesign.com/app/webroot/files/file/60839674704.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/nudedoxijidi.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/xajezigabi.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614576412b549---vulavex.pdfIn PDF document text
    • https://drivetripper.com/userfiles2020/files/rijafuvakomegepozuliwi.pdfIn PDF document text
    • http://maimungkorn.com/UserFiles/file/fezumim.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/3165d294b49eb0768d189fb3c8dd3944/gajon.pdfIn PDF document text
    • http://wangguanhardware.com/userfiles/file/vadufisufugimogepapere.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/90807770437.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/79027352981.pdfIn PDF document text
    • https://alcoquimicos.com/ckfinder/userfiles/files/vufefotogusigizefufuko.pdfIn PDF document text
    • https://marblobaths.ph/app/webroot/img/files/lunatoxivufusezaxekaki.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/52391922524.pdfIn PDF document text
    • http://bxbrdh.marketsearching.com/upload/files/69464934629.pdfIn PDF document text
    • http://everbeenmagnet.com/js/upfiles/files/nepexamadipufixa.pdfIn PDF document text
    • https://kawanmto.com/contents/files/labemakitobovuribubanako.pdfIn PDF document text
    • http://colleges-in-tamilnadu.com/FCKeditor/userfiles/file/maximufewaxejokulat.pdfIn PDF document text
    • http://biplano.eu/userfiles/files/11841336966.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://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_off0000c439.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC439 17924 bytes
SHA-256: aef6e48afbaf89ff13ffae49c05fdf26ba0b6305a328067a33c57d0a0a07a72c
font_01_sfnt_off0000f322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF322 10744 bytes
SHA-256: 3ed89695f6e95f2197f39d079d8f393e14d93d33b4ec08fa72efa7b978788724
font_02_sfnt_off00010b8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B8F 16540 bytes
SHA-256: 45015263e28dbf00792e0fa83ae0fb9123af5110209f191c00797c49350166ef