Malicious PDF — malware analysis report

Static analysis result for SHA-256 e353331cccd6b08f…

MALICIOUS

PDF

71.9 KB Created: 2021-06-04 20:26:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: c84ac8044acfde6357e471bd2eae2e58 SHA-1: fa8fc4d6ab0b2a13462e0e451f6a29a806be8bcb SHA-256: e353331cccd6b08f6263615715a9fd735497bf30576c9eefb8d15600adc3235e
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous compromised WordPress sites and disposable hosting domains, likely to distribute further malicious content or phishing pages. The presence of embedded URLs and the structure of the document suggest it is part of a phishing campaign, potentially using the lure of a 'book pdf' to entice downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://synerhu.ru/uplcv?utm_term=como+aprender+ingles+livro+pdf PDF link annotation
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/6f016a62c9fab5e3274097afbe58ba06/bujupaxawexalid.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/xugibifojidalazitisisad.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160804ac72c5ba---pivazizet.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/suxovumifoxerobaze.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae9c63f3867---99452262911.pdfIn PDF document text
    • http://thehawthornnyc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841bdd91a82---93695650051.pdfIn PDF document text
    • https://lymfologi.se/anvandarbilder/221/files/90402987746.pdfIn PDF document text
    • https://amerismithenterprises.com/wp-content/plugins/super-forms/uploads/php/files/cc040377f1d94a0d0e837d923c1a4e77/34668751935.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/wazibawakubikexido.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/3fddc64312c32dfb725b8b4a4eaccadd/rejoxurofirubozipu.pdfIn PDF document text
    • https://fanaf.comarticle_ressources/file/59647594087.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cf5c7aec1e---98895712399.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/16094353e5e3d8---24822124158.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/f3130192679f59f565eeef2906fc6c60/81607782304.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB39 5152 bytes
SHA-256: 523cef3f3dac0b76aded2eff63f5dfccaa52f9a899df64ed653ce56d3519f623
font_01_sfnt_off0000dca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA5 12412 bytes
SHA-256: 10151c39b8016dc8a07a9649f2cfffd1d3df07d9af5215c775c1c63c90c7e307
font_02_sfnt_off000102b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B0 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176