Malicious PDF — malware analysis report

Static analysis result for SHA-256 a73bc766db65b2ae…

MALICIOUS

PDF

80.6 KB Created: 2021-06-12 15:35:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 1a2eac1dc8c9748fcc4660753d724092 SHA-1: 4c91fb484c591075642d1c6bc7350a7c708b6164 SHA-256: a73bc766db65b2ae3ee6ff8856837535ef01f122dbd80d4b28b8dc8dbe09494c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common method for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nomylo.ru/uplcv?utm_term=shelby+gt500+super+snake+horsepower PDF link annotation
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/be4bab19eec7f589058ebd774fdeb1e0/fisixasafulikag.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/dpvh5njv89faddiegeplu5ifds/zidetaduvusobogidozebepur.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2d650e40a---fujebofemebov.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160bb39896c06d---wexujujegi.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/zojoxenumuzuvemati.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2c66d4b71---33797070040.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/e984ad20cea6ed5f61055772e59bcbfd/20452382757.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078e2c560781---67737245412.pdfIn PDF document text
    • https://t2sc.me/userfiles/rusupigekifakilas.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/94116f90ee1d5c15ca1e2d27b8a0124f/65926907957.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b3772f235---70551376036.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/jirimi.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084083f1fad9---mugepasazewuzasada.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a35aec932a2---63947874947.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/45070504163.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED42 5680 bytes
SHA-256: cc1a0ca6c683bdc5f94a81556d0e523829890b8c4e2bccf786e9da204536c50a
font_01_sfnt_off000100a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A7 11312 bytes
SHA-256: 04a15c3957f45edc9080cd26e107d89ed9a30915ce9b27c0abbd86cd47a36507
font_02_sfnt_off0001273f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273F 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3