Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bc37ef808393f2e…

MALICIOUS

PDF

89.1 KB Created: 2021-09-22 14:15:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5b7190962c74606c59e148a2ec9f96eb SHA-1: f3cebccedf31ad09864b88d92d5fd00c6e6cd177 SHA-256: 9bc37ef808393f2ed7c3d2893d58be61c1ea3312179b12c9643fc2d767a9a1e4
156 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 domains associated with link farms or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO abuse. The document body is heavily obfuscated and does not provide direct user-facing content, but the overall structure and URL distribution suggest a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://rlangkhan.com/upload/userfiles/files/fiziduxodofudemefiworive.pdf In PDF document text
    • http://bagodilovaspark.hu/userfiles/file/rowimuwiwo.pdfIn PDF document text
    • http://szjwwj.com/userfiles/file///54792609042.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/161384050dcbcf---xorazebegeniwopodubilude.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/3432976482.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/mofuladuwugometaxe.pdfIn PDF document text
    • https://takipbizde.com/calisma2/files/uploads/jororonizumukipovu.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/679be4ef98ebb97c9cf0277247ee055c/jimegigofe.pdfIn PDF document text
    • https://interangkorcondominium.com/userfiles/file/51849434267.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210918224923.pdfIn PDF document text
    • https://www.myjamaicais.com/wp-content/plugins/super-forms/uploads/php/files/3935228b69047fa79685ce691f294d60/zafoxetokepubane.pdfIn PDF document text
    • https://ahirealty.in/admin/userfiles/files/54448158375.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/zigotiw.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210917165611_1963555538.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/fizetinofeguzinavig.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/57748476650.pdfIn PDF document text
    • http://veitali.com/upload/files/totenix.pdfIn PDF document text
    • http://ge-mak.com/files/jefojozufuwutalezovejokod.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/tozewutalagazat.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/jogos.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/lejofojivatetadoful.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e69a6a89ca---72283688711.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=tps+system+examplesPDF 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_off0000fb7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB7B 17432 bytes
SHA-256: 33155e1ae333d0d466ca2be0b3ff4f0e0d0bf1020d8b5426d3d8b031512fa7e1
font_01_sfnt_off00012858.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12858 10176 bytes
SHA-256: 154d1a0e48db66207bd1fdd352b3632dea789ecb4651c2b226243341cf1ac4ae
font_02_sfnt_off00013f43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1