Malicious PDF — malware analysis report

Static analysis result for SHA-256 2316a6071de035de…

MALICIOUS

PDF

78.6 KB Created: 2021-09-09 02:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 230e527921010d3610e893a58f5b64e5 SHA-1: 29ed366f3856cb435f3b9b0bcc50d7c562d857ca SHA-256: 2316a6071de035de57dc5a7767f1175ca862e9ac2bc6164cbf79ae1b35f59576
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple PDF link farm heuristics supports this assessment. No scripts were extracted, but the overall structure suggests a malicious redirection or phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://rld-carbon.ru/file/19659032797.pdf In PDF document text
    • https://ihappywash.com/uploads/files/202109081124197813.pdfIn PDF document text
    • http://kientrucnhacuagio.com/upload/files/wexixefejerodoronatij.pdfIn PDF document text
    • http://tolltisztitas.eu/userfiles/files/kibusulebisejutu.pdfIn PDF document text
    • http://all-paca.com/ckeditor/ckfinder/core/connector/php/uploads/files/mojakuzezamaxopimizu.pdfIn PDF document text
    • https://bdata.vn/upload/files/85766549760.pdfIn PDF document text
    • http://ltpbetel.ro/userfiles/file/mosomedutefasemitefupo.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3e61aaf10---wipukafore.pdfIn PDF document text
    • http://gomientrung.vn/uploads/image/files/komipilojoduzuzexevuvire.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/2653720088.pdfIn PDF document text
    • https://wmu24.ru/media/file/mufiramajemilulipa.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/94400691962.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132f09e1062b---66390616785.pdfIn PDF document text
    • http://futureinfashion.com/ckfinder/userfiles/files/mibidejopejopaw.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/fulololomubufujiluxu.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613048d3bae01---dikibupiruw.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/f4473ef461e284fc2abc6e65da2cb4bf/kubatijoper.pdfIn PDF document text
    • http://aktifimmo.lu/userfiles/files/34041892263.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210905_264E9382928729C6.pdfIn PDF document text
    • https://suadienlanhhanoi.net/upload/files/94815142846.pdfIn PDF document text
    • http://e-store-sys.com/userfiles/file/jatewevojapoxusovutid.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/16074854567.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/94445568334.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=dexguard+root+detectionPDF 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_off0000cd4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD4B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e55d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE55D 18172 bytes
SHA-256: 0ba79f15857cf44228deb5f43a1caa45dad107cbc82f1990e68cfb3af1d917ac
font_02_sfnt_off000114e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E9 10532 bytes
SHA-256: eda2605f70a384ec09d9171550905ce6d934cdb2dbce37ffe96e4c7bd6197e0e