Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f639407171b78e3…

MALICIOUS

PDF

70.8 KB Created: 2021-06-18 23:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 4cd9b55d9f8b1987dce0e7144b2b5168 SHA-1: a42adbc86ba9413be5ac8b67b5a4eb5f9cbc7780 SHA-256: 4f639407171b78e300739312a7b9cf9385af0b12033bb4429b216f4af595bad4
164 Risk Score

Malware Insights

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

The PDF contains multiple links pointing to compromised WordPress sites, likely serving as a link farm for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing and potentially trojan delivery. The document body, though heavily obfuscated, suggests a lure related to 'Chromecast setup', aiming to trick users into clicking the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://philabc.ru/uplcv?utm_term=how+to+setup+wifi+chromecast PDF link annotation
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/16073467fbd0ab---vedirugewanag.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081ae96031a8---wexitovineliwividakuweli.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0b4d038d8---11751589572.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/piig9tfblpj1cpda8tu1neg6a1/39425444747.pdfIn PDF document text
    • http://saokienviet.com/uploads/image/files/46697782931.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/45335154510.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160818de7cb618---85192307228.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085a07c389c8---10550699769.pdfIn PDF document text
    • https://travolution.travel/wp-content/plugins/super-forms/uploads/php/files/2a684317dae62c062ebeddd7d0c12da7/11289712600.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/f3b5fb9901dda67e924a48b85be94446/79863249999.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e0dd984675---wusumopuso.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8469480f91---resilaxazok.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1495a451b---93397735841.pdfIn PDF document text
    • https://visionbrindes.com/admin/fckeditor/userfiles/file/24133867680.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_off0000d713.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD713 5276 bytes
SHA-256: a203f1ce9f08978c6c6074b385bf70e46b8d9dba3a53e395dbb207af1906e513
font_01_sfnt_off0000e8ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8ED 10988 bytes
SHA-256: 4993170cc09058b4a0fe98ff3aad041da9d0e0d4714a0fcbb7fbc45193c4c11f