Malicious PDF — malware analysis report

Static analysis result for SHA-256 a771903daed99c6b…

MALICIOUS

PDF

84.9 KB Created: 2021-09-11 23:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: a754e53a10d04a9345368b713c47c12f SHA-1: 20454c6ab83da9e30afb6a3bd45a538b1804fea5 SHA-256: a771903daed99c6bfb37ae9d350049af419c27f638ac952ae236220a95985cb2
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains embedded JavaScript and multiple external links, some pointing to compromised WordPress sites and disposable hosting, suggesting it's designed to redirect users to malicious content or download further payloads. The heuristic 'SE_INVOICE_LURE' indicates the document's content is likely a deceptive lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 8

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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 http://re-media.ru/foto/ck/files/89253103547.pdf In PDF document text
    • http://deaprogettazioni.it/userfiles/files/30682281074.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/bilobibajazad.pdfIn PDF document text
    • http://ucokampen.com/media/files/13501511643.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/0d95fdb3d1e549ced3b3cb7dce86b8cf/90417942719.pdfIn PDF document text
    • http://millecolori.it/images/file/34313000855.pdfIn PDF document text
    • http://dyccpharma.com/upload/files/35037220732.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///boneporene.pdfIn PDF document text
    • http://upasamed.org/Content/uploads/files/75040395957.pdfIn PDF document text
    • http://slavutich-media.ru/userfiles/file/lujerogopumevaredafape.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/7a175c38a7b227df12fc6841322335fe/mivuzaperotoraveruxadipo.pdfIn PDF document text
    • https://patoman.ro/ckfinder/userfiles/files/vogupomuludal.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/pesejutemolapevo.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/pumugekedarabago.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/66872572015.pdfIn PDF document text
    • http://eastindiaspray.com/suvra/eastindia_spray/files/werevanutepilobux.pdfIn PDF document text
    • https://fiscalonline.eu/app/webroot/files/userfiles/files/nuwirobalukar.pdfIn PDF document text
    • http://appextskihjthj.handysociality.com/upload/files/96464548300.pdfIn PDF document text
    • http://ux02.wadhost.com/js/ckfinder/userfiles/files/18444008177.pdfIn PDF document text
    • http://888spirits.com/userfiles/file/lekometiripora.pdfIn PDF document text
    • http://homeshopeez.com/uploaded_files/userfiles/files/pakawesumapizesifobik.pdfIn PDF document text
    • http://briztravel.com/upload/files/65239280261.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b2cfd4a3b---muduwivanozililoze.pdfIn PDF document text
    • http://eraldocomo.it/userfiles/files/nuburefevibone.pdfIn PDF document text
    • http://orthodoxvaidikasanghom.org/userfiles/file/12749835439.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/dorigatixa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=personal+budget+app+androidPDF link annotation
    • 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_off0000e822.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE822 10808 bytes
SHA-256: 52801d3f2fcdefff494214e7ecbd61dcd3605b2957b6ab07624577b55c9cc3df
font_01_sfnt_off000100ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000118cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118CC 17312 bytes
SHA-256: f9955cfbc6cc60c6847bd456a584a4dda2413e851d6803272f0dc8824e1876d2