Malicious PDF — malware analysis report

Static analysis result for SHA-256 f439e17e807eaa05…

MALICIOUS

PDF

81.6 KB Created: 2021-09-10 07:32:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f4143e0d6bbb941f04377d962973263a SHA-1: 6315241fe24ad05e300ebea1b00ccddd17a4dcba SHA-256: f439e17e807eaa05adb23600b023d4e21660dfb59e5f240200839130a3eeadf4
164 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 compromised CMS uploads and disposable hosting sites, likely to facilitate further infection. The presence of a 'download button' lure further supports a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/jj6klkoveg1kjb6h3t7mu84hie/joxusipifepudidifetivi.pdf In PDF document text
    • https://cuatudongbinhduong.net/uploads/files/49353921669.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/498deb7235b8590dd31eabb8ffbd6ce5/20040526405.pdfIn PDF document text
    • http://colantuono.it/userfiles/files/36290093956.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/xiwamosamomavododukas.pdfIn PDF document text
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/3ca8e24c95275551f048ea3f7cfe0135/xugisotuxamigiju.pdfIn PDF document text
    • https://ppntassone.it/dati/upload/file/kujemubisukakivep.pdfIn PDF document text
    • http://katour.ru/admin/ckfinder/userfiles/files/21803137304.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/duzapenubowejo.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/63096496010.pdfIn PDF document text
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/56027757342.pdfIn PDF document text
    • https://kisikana.hr/UserFiles/files/bebeme.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/49593101825.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/4212769712.pdfIn PDF document text
    • http://nelly-design.ru/upload/files/sobisirove.pdfIn PDF document text
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ace915bbc5---penatefuwebekodupojuv.pdfIn PDF document text
    • http://retailcop.ca/files/95672119907.pdfIn PDF document text
    • http://ccshecea.org/upload/files/lovunopowasepevede.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/27a02c8ea426340a84b64a6157afd91a/xijozaxukegajokesumo.pdfIn PDF document text
    • https://estoniapools.com/contents/files/63518816030.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161312aa97c8b6---zepuruzebenabitugibada.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613112bf2c0f2---4472159540.pdfIn PDF document text
    • http://gma.ge/admin/ckeditor/ckfinder/userfiles/files/35580862703.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/tuvokig.pdfIn PDF document text
    • http://emeat.ru/var/files/27173625401.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=nda+exam+2020+answer+keyPDF 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_off0000d8b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8B4 10668 bytes
SHA-256: b3af44b48cdfe559da2382edc54faa60995697e7e70056f3162cdea85883216f
font_01_sfnt_off0000f144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF144 18484 bytes
SHA-256: 00e3405d3be50aa4ebd6389546b11c3bdad93c71affe5f4fb7ce39b6d01a602e
font_02_sfnt_off00012108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12108 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1