Malicious PDF — malware analysis report

Static analysis result for SHA-256 56fa8fb253d6cd66…

MALICIOUS

PDF

83.0 KB Created: 2021-09-01 13:13:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c0ccf1a103ecce25e23aa7b15c1ebde2 SHA-1: 1074de28fdfc8914bb3a49c7783045eab5b17ec0 SHA-256: 56fa8fb253d6cd666f933dbe9a1081a6a7dd302a8e1bcf16f27902bc2719886b
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for malicious PDFs. Heuristics indicate the PDF acts as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The ML classifier strongly flags this PDF as malicious, suggesting it's designed to lead users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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 http://ijdssymposium.eu/upload/46727659386.pdf In PDF document text
    • https://luxesystem.site/js/ckfinder/userfiles/files/biwugapawegeronusoma.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/mizugofoxuwinisefalilav.pdfIn PDF document text
    • http://premiumcsp.com/uploads/files/vevaxowovewodonivej.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/fajipirilatorizijoz.pdfIn PDF document text
    • http://howsonfamilyreunion.com/clients/5/57/57b8fe7d350e782a16e6afc8bdcd6467/File/xizajasuses.pdfIn PDF document text
    • http://obras.ru/sites/default/files/uploads/nenaxalanamikofusub.pdfIn PDF document text
    • http://1960ihs.com/clients/e/e0/e0b58928a48036c9af8d6cfc9cffdd99/File/pulozisitutuwuweput.pdfIn PDF document text
    • http://castudio.eu/userfiles/files/49193839614.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a5be401e0---84604044098.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/24518509697.pdfIn PDF document text
    • http://whatdwellswithin.com/file/bunubotebobulukiwuwex.pdfIn PDF document text
    • http://nwatchonline.com/userfiles/file/65513892884.pdfIn PDF document text
    • http://zerosquareonline.com/file/15560590878.pdfIn PDF document text
    • http://lroundup.com/clients/d/d7/d7466da0ad72d96b64793f89c518a0d9/File/jixekez.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/8c2a97eddaf0f674734dea9b966236d1/60838181300.pdfIn PDF document text
    • https://nscs.org/wp-content/plugins/super-forms/uploads/php/files/225b9a70495884c2e172202132d26984/rakasarun.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/tujarekejizipojanigod.pdfIn PDF document text
    • http://staceyasp.com/UserFiles/file/62515565010.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/eb3bda3b71ce3c620f8952a6d9951b5b/94321212513.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=canon+d90+user+manualPDF 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_off0000df6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6F 10640 bytes
SHA-256: 53c332a1fbfa2e1fa4acedc75a27d5ed9e9910fee5f7bb1e2db06bca180466e9
font_01_sfnt_off0000f7c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C7 17784 bytes
SHA-256: 8c92b2b8472b33cc9963bf2f9e12c781c93542278d78198245e06f24e0e60ef5
font_02_sfnt_off000125fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1