Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3aa9ae7278506c8…

MALICIOUS

PDF

85.0 KB Created: 2021-09-17 22:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 00b2d694a781dd82320d04a155d1dcf1 SHA-1: 9b2d1ed00567e23a695585e5861a7593c5a55f71 SHA-256: b3aa9ae7278506c8f8e27d2f60e5a1e9097ff9d8148a0d6364a5f0ef769e76df
164 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 compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://laborke.ru/uplcv?utm_term=speedtest+app+android
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/duwowexijenofavana.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/6c84ec48cbdb15d0ade7b7cfcdeedbf7/93957844653.pdf
    • https://confeccionesruiz.cl/UserFiles/File/dukoze.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143e6f66d5fd---31466768151.pdf
    • http://proallprint.com/userfiles/files/zubejaziwowu.pdf
    • https://www.willmarshelter.com/ckfinder/userfiles/files/gudusomuk.pdf
    • http://benedictinoselrosal.org/ckfinder/userfiles/files/94202101942.pdf
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161321d2a449c5---rufinefepusoverijuzorefeg.pdf
    • http://jszl-rolls.com/filespath/files/20210914095603.pdf
    • https://skywaynepal.com/userfiles/file/1616613554.pdf
    • http://autodilykanka.cz/cmsimple/images/file/80101415795.pdf
    • http://unsersohn.ch/images/file/dobilarotodi.pdf
    • http://juentai.com/userfiles/files/39569194147.pdf
    • http://spain-ex.com/images/blog/file/fuwefajigij.pdf
    • http://knipia.com/userfiles/file/xifajirarovefobomeporuxe.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130817833b6b---retomapovoripu.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614024eadcab8---wadigojudug.pdf
    • https://baatco.com/ckfinder/userfiles/files/77762054452.pdf
    • http://secureyun.cn/uploadfile/file///2021091402595998.pdf
    • http://to-kajihan.net/js/upload/files/foxebutukotanivudujeruli.pdf
    • http://snabsz.ru/ckfinder/userfiles/files/muzepibiguvoguvesap.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7a2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A2 16792 bytes
font_01_sfnt_off0000ffb4.bin
7277b29c4e8131ec9df78e441ee9c62668c60791ce63ec0d66a8bc3955162443
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFB4 18264 bytes
font_02_sfnt_off00012ed2.bin
bc2bfd1556921c4df4b1c26a2074479e20f6682d0967771b1f5315792edc74a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x12ED2 10412 bytes