Malicious PDF — malware analysis report

Static analysis result for SHA-256 f51aaf9c7650e9d3…

MALICIOUS

PDF

85.0 KB Created: 2021-09-17 08:18:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f88840db562cf9521c87d31ef3e6cbc4 SHA-1: b218977da85dcf7df0f49d5eee8eb7f953908b78 SHA-256: f51aaf9c7650e9d3b82837e4379f870458e5a0b18ff17393748c19f2a9c38ae9
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 a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to potentially compromised or disposable hosting sites. These links are likely designed to lure users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://aadcnfgl.netsociality.com/upload/files/7423975713.pdf In PDF document text
    • https://channeloflove.com/ckfinder/userfiles/files/migodopaxovexunufabewu.pdfIn PDF document text
    • http://thietbibepnhahang.net/media/files/93429859223.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/fepekevopal.pdfIn PDF document text
    • http://sirmamedia.com/ckfinder/userfiles/files/42692093241.pdfIn PDF document text
    • https://maviet.vn/upload/files/xisas.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/bibewuketovefazekirerasuw.pdfIn PDF document text
    • http://www.rupankar.com/fckimages/file/14918686846.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/dibugeku.pdfIn PDF document text
    • http://marathon-gexin.com/Uploadfiles/files/puzezisatumezulodo.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141da35289be---silesifusonobusun.pdfIn PDF document text
    • https://yenicekentkaplicasi.com/userfiles/file/wiweji.pdfIn PDF document text
    • https://chatham-ebenezer.ckdomain.com/uploads/userfiles/files/dirabetapevakivimizared.pdfIn PDF document text
    • http://avsa.org/sites/default/files/images/files/34618008619.pdfIn PDF document text
    • http://woodwaysindia.com/uploads/perisanoviboka.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/77b9ce52f326e21e99ecf2eb5fe25ee6/xexuwomojup.pdfIn PDF document text
    • https://benqmusicworkshop.com/fupload/file/sijefodalifubuloju.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/e05ad9913a865e53c0c77b01d40c4d8f/68478025796.pdfIn PDF document text
    • http://ambartakip.net/belgeler/file/vupitokolibadenoxumona.pdfIn PDF document text
    • http://anais.terminarz.online/kosmetyczka/krakow/files/14237404213.pdfIn PDF document text
    • http://sobateracota.ro/mm/file/14702207346.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/nc46d79e7almeu3t2an7glimq2/66179227008.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+clear+rom+memory+in+androidPDF 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_off0000e7e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7E9 17624 bytes
SHA-256: cf8e9a1ef47ae4716cd6e16905e932e660810e2df33da1861852ac10f1514531
font_01_sfnt_off000115c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012de0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DE0 10556 bytes
SHA-256: e255977b375f628552cb02b8b75dc1cc43300697875105ce456b242d36141636