Malicious PDF — malware analysis report

Static analysis result for SHA-256 c88f344bdecec4e7…

MALICIOUS

PDF

69.3 KB Created: 2021-09-19 10:01:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d7547ab59237f78c3beccafa6096b164 SHA-1: be7af11c39add07a94d0b6c864073ca2cb2793fb SHA-256: c88f344bdecec4e7f92ed93474c8c9f3ee4e35458890d848f1e8761e1f2375c6
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document is identified as malicious by multiple heuristics and an ML classifier, including a critical ClamAV detection for Pdf.Phishing.Trojan. The document is structured as an image-only lure, typical of phishing campaigns, and contains embedded JavaScript. It also functions as a link farm, directing users to various external URLs, one of which is a redirector with a 'download subway surfers' query parameter, suggesting a lure to download potentially unwanted or malicious software.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://infrive.ru/uplcv?utm_term=download+subway+surfers+for+android+phone PDF link annotation
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/94551705503.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/vuvikekivaxitezenuveli.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/1613a620187ea1---40110637366.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/tafix.pdfIn PDF document text
    • http://avandcie-energy.fr/ckfinder/userfiles/files/fefuxavesajazasimalox.pdfIn PDF document text
    • https://hotelangela.hu/userfiles/file/4442476026.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/kulopaxedelejolafavaro.pdfIn PDF document text
    • https://www.wroclawmodelshow.pl/ckfinder/userfiles/files/31563694169.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/18557105012.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/20930707373.pdfIn PDF document text
    • http://tylincms.com/userfiles/files/dedekeviselavigibadujenin.pdfIn PDF document text
    • http://vipacademy.org/userfiles/file/xulivikuzujilojebupoxulum.pdfIn PDF document text
    • http://tccsrl.org/userfiles/files/88408069555.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/56357164973.pdfIn PDF document text
    • http://ph-easycome.com/userfiles/file/samumezubipudobote.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/bakewatonaruzivive.pdfIn PDF document text
    • http://bobiniauto.com/userfiles/file/35010093477.pdfIn PDF document text
    • https://erdemlerkoleji.com/resimler/files/43191076449.pdfIn PDF document text
    • http://tuning-zone.eu/userfiles/file/bezojagodologatoruwor.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/lexudoboxipodiku.pdfIn PDF document text
    • https://brianhigbielaw.com/UserFiles/file/kepizudirudakivatom.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/jajuguvuj.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/75474189043.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/2021090711060123709.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_off0000b311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB311 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB28 10936 bytes
SHA-256: 66cf4de64c9c30590a0400b552d6cff6d3fd58a25e9452fc3f568696fcd0db47
font_02_sfnt_off0000e441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE441 14060 bytes
SHA-256: b290703a006177bb2d0db9d64ee5b7064c5d4f30fa6dfc5ab1c6772734cea0dd