Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b5149997ec6c5be…

MALICIOUS

PDF

77.7 KB Created: 2021-09-05 13:13:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9e563895758f471c8d520725123afa3b SHA-1: df81d417a72853f6954b0509fb55bcd45f8d7065 SHA-256: 5b5149997ec6c5be62eff8577067cfe0357364e359975ca5917921f533df2fa9
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of its harmful intent. No scripts were extracted, and the document body was unreadable, so the analysis relies on the URL heuristics and ML detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • 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://infrive.ru/uplcv?utm_term=statistics+important+formulas+pdf PDF link annotation
    • https://ksboutlet.com/file/files/63573013419.pdfIn PDF document text
    • https://airtelco.com/data/users/_/email/files/xetisifo.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/be318273981533e6714b8cca6ee6bde8/topuxamegakimawil.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fb4cc8145f---8493335353.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607344ea5f644---10465268503.pdfIn PDF document text
    • http://prmakeup.com/Image/files/japikukanagogeze.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/302rvu0ujpssclqfogd9uo3ms0/mafulorudaposomodifabo.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b004ef29c6---zedefuvoxo.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a95127c7c7c---26283138984.pdfIn PDF document text
    • https://gkscam.com/userfiles/file/mojos.pdfIn PDF document text
    • http://orvosvalaszto.hu/uploads/files/50640062965.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/f1204627b26a9f5da2ef957a1945158d/sudik.pdfIn PDF document text
    • https://hyosung-gulf.com/uploads/file/8614644155.pdfIn PDF document text
    • https://angkoronetour.com/userfiles/file/57032623981.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16102820b4df08---kilujanemesobozez.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/32085505087.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c265b35ad43---55353822297.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160c3affd29fbb---47835377459.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/38910144929.pdfIn PDF document text
    • https://badrivishal.com/media/26518824254.pdfIn PDF document text
    • http://vakoplus.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/43989012657.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/lomamuke.pdfIn 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://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_off0000caf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAF9 17612 bytes
SHA-256: 687875b02975f68c94dec8ac5bb0da619b77e87856b89c1104b9f386193eeea6
font_01_sfnt_off0000f878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF878 10824 bytes
SHA-256: 9406156e4c0ead488c93644dadc9fbfe98f8709a27bc7eb0b42a1f9f534b8a1d
font_02_sfnt_off0001115d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1115D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1