Malicious PDF — malware analysis report

Static analysis result for SHA-256 35e3c4b516add821…

MALICIOUS

PDF

80.3 KB Created: 2021-06-09 07:56:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: e4da6e4de2143528e196fa4d2d6e2424 SHA-1: 143037ad78d7425a0b58465490f53a79d92fb7eb SHA-256: 35e3c4b516add821c65525765396930c78300d5d34209bbf0bb23954daa81bb0
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identify it as a link farm on disposable hosting, with URLs pointing to compromised CMS uploads and external download pages. The presence of embedded URLs and the nature of the heuristics suggest the PDF is intended to trick users into downloading further malicious content, likely through a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://inwebjor.ru/uplcv?utm_term=ml+obb+file+download PDF link annotation
    • http://mkngsp.ru/upload/files/25771830958.pdfIn PDF document text
    • http://www.predoisiasociatii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160960748aeed2---95906722804.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9f8bd4e5a---pesebibek.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/vtb35t3app84aadadffsped9ra/9277741115.pdfIn PDF document text
    • https://actor-conseil.com/files/file/nefidazi.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/1745500012df267974a7505a069fb50e/xifuxeseruweraxirotozot.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/950d3bdc08f13cd3ace2837acd8bba5f/30153982367.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607549acc877f---91473116683.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b48690bf662---gofetu.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077c5ae1b8d7---37354127173.pdfIn PDF document text
    • https://avvocatoboretti.it/file/famadezilurovajaxudezafot.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/poraxagej.pdfIn PDF document text
    • http://firegallery.ru/img/upload/838906454.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/loboxulewusisadel.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/c45f64be04ff308b6a63ce772e6a6676/9671393477.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/5b1b097ce269e25d1cbe8eff79dd54b7/kodenodawuniserisi.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/roremog.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/volor.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/fcaa1ba97af1ab27efaf9b4b35c28bd7/figidulasutubu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f1b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B6 4864 bytes
SHA-256: d0f1cbe0fecfc8b2e080d4e62d81ec4663898364dacc1d00133388b30b25196c
font_01_sfnt_off00010274.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10274 22128 bytes
SHA-256: c53be4a47dfec465c5b6b0fabde41213090d2e7dfe84840b69d30aebe194b9eb