Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec26cb4ea007dca9…

MALICIOUS

PDF

83.0 KB Created: 2021-09-11 15:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 78fb359b8aa210dad42f0f36fd5f0d83 SHA-1: 2a571d2a577edda57603782b9bea52c470a13d2a SHA-256: ec26cb4ea007dca954faa2a74831af509eab24b8bf3a1e50cbc73265484b6ac3
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The document functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. These links are likely intended to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gpmpoolandspa.com/ckfinder/userfiles/files/bobujovu.pdf In PDF document text
    • https://alves.bg/ckfinder/userfiles/files/22363157961.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/78777367463.pdfIn PDF document text
    • http://ikra-ekb.ru/files/fckeditor/file/32152547343.pdfIn PDF document text
    • http://conditum.nl/userfiles/file/nubezutedaziwewilopud.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16135b38bc36ea---xofuxuxu.pdfIn PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210911_120455.pdfIn PDF document text
    • http://sh-songshi.com/admin/upimg/file///48455126209.pdfIn PDF document text
    • http://classicalgardenfountains.com/uplds/file/zevipam.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/2d773319f1761058065e5fc0b88c0967/kixubifi.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16132c82939d05---48006861040.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133dedf19744---wevuwexawidumujapexow.pdfIn PDF document text
    • https://beta.nhatthiengroup.com/files/uploaded/files/fodekifipepipezelufijakif.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/73197683562.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffce588dd3---13876971399.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/vatoxafutodineg.pdfIn PDF document text
    • https://muahohangnhat.com/app/webroot/uploads/files/98588908607.pdfIn PDF document text
    • http://hkalc.com/userfiles/kegibemaliwonase.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134df031aa25---30798741473.pdfIn PDF document text
    • http://briztravel.com/upload/files/70478911728.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/48918684071.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/wiwinoxosijen.pdfIn PDF document text
    • http://sov.tranovice.org/webpagebuilder/ckfinder/userfiles/files/kerifedamowebawopirilex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=million+billion+trillion+quadrillion+quintillion+sextillion+septillion+octillionPDF 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_off0000ddb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB2 10988 bytes
SHA-256: 8ac93da3486d99eb3a2f102f91bbdb5d5b3cbbe832d62fbcd6cd8ba258e4adc6
font_01_sfnt_off0000f6eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6EB 18020 bytes
SHA-256: 59a0e4e8939910c607b0459c81c732ed088a0677708acb2a75c9349e8b9f57e4
font_02_sfnt_off00012569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12569 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1