Malicious PDF — malware analysis report

Static analysis result for SHA-256 303beb5a2d9ba618…

MALICIOUS

PDF

69.2 KB Created: 2021-06-18 10:19:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 32b52ac72cce1d5c20fee2c95e842247 SHA-1: 94a2a40a42ff799d06317c7efaf392abb3dbb51f SHA-256: 303beb5a2d9ba61888f19b9678e042771418a3d3b006a62183d35c4256faec63
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload storage locations and other disposable hosting sites. The embedded URLs suggest a phishing or malware distribution scheme, likely disguised as a worksheet to lure victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crewmak.ru/uplcv?utm_term=rational+algebraic+expressions+grade+8+worksheet PDF link annotation
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/78d6f5aacf231ad49b443dc0fc9ccd01/59628200490.pdfIn PDF document text
    • https://debcopharma.com/userfiles/file/depat.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ac1fdcb910---kebosafovuvunovoviv.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/bea37e4120d996081a53cf680cbdab97/66985811830.pdfIn PDF document text
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/3p35nej2rd4q15bohncfrjcum1/matefonoliwiretexalafiwi.pdfIn PDF document text
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1608404c9d817f---81986327308.pdfIn PDF document text
    • https://zegabilisim.com/calisma2/files/uploads/kasebubifuv.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609711762310b---vuravigano.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608747e5d4688---8174318115.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/nopupopowegarujiwovetunej.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/381a6fbe399e27e74b511471c69dc79c/gunexirebowenenu.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file/%5C/20210524224451_493769128.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/kn438jtmhechuuf8db9580r2p0/72622716442.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/c847915b3f71143f6bfcd540b0a4afde/bunejemusipakozader.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/2cc8f40a5f24fa213ae44346730926ad/jetuduzano.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/54504736887.pdfIn PDF document text
    • http://sumtinathholidays.com/admin/uploadfiles/file/paboporovigoboma.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/fe949db25828c99bf17262dc6b01aa93/14079524040.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDED 5900 bytes
SHA-256: 502c5f71b164b2dd1f04041a24ad09e49511c2fd8d2a30528e2810a120c95c6c
font_01_sfnt_off0000e215.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE215 11028 bytes
SHA-256: d2bf766f86364aa740ba833bde6db374f7545f06ebff67887b0e954030671941