Malicious PDF — malware analysis report

Static analysis result for SHA-256 d033b77bf592d9ec…

MALICIOUS

PDF

73.0 KB Created: 2021-09-20 22:34:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 2dabeca181680f43774eea692714b0a9 SHA-1: 8314beb6db1ccaaf52a75f269a2acb3785cf7517 SHA-256: d033b77bf592d9ec141716ba72201a735be85c686a100cb3847d0d65de189a01
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of external URIs and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://catamma.ru/uplcv?utm_term=what+is+a+good+music+downloader+app+for+android PDF link annotation
    • http://pereplanirovkaoblast.ru/pict/file/zulogexexujiwo.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1f6f3d31a---10900111998.pdfIn PDF document text
    • https://bharatbiodiesel.com/userfiles/file/xuruzakupenafuxewedewuwi.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd7d8e8e95---14318133475.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210913182131.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/zilopebifiz.pdfIn PDF document text
    • http://urbanposthotel.com/admin/ckfinder/userfiles/files/81498720155.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/gojapimolujupukidelusofag.pdfIn PDF document text
    • http://venkateshservices.com/uploads/wutubeligudaxugototibex.pdfIn PDF document text
    • https://tonerihned.cz/userfiles/file/jimajiwanuzebegi.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210902_032513.pdfIn PDF document text
    • https://luathoanghuy.com/uploads/files/8632243658.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/tekefiwekel.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/nuwumukurasaduparuxi.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16146016788b88---vajofelivujapig.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/betubegisudati.pdfIn PDF document text
    • http://exito-opakowania.pl/userfiles/file/28287817776.pdfIn PDF document text
    • http://www.pavimentosyreformasferlu.es/ckfinder/userfiles/files/85443814222.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/38850098075.pdfIn PDF document text
    • https://brune-schmuckwerk.de/ckfinder/userfiles/files/61591633531.pdfIn PDF document text
    • http://prestopc.it/upload/file/54135702459.pdfIn PDF document text
    • https://eguiders.com/uploads/71923576666.pdfIn PDF document text
    • http://studiodara.eu/userfiles/files/kagunobiruxevo.pdfIn 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://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_off0000b9c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C6 16504 bytes
SHA-256: 5b245d2f04828bf426e8249e1ff47a29dbf7b6f1d9d3d3181be9416f4fc7b96d
font_01_sfnt_off0000e3e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E0 11244 bytes
SHA-256: 05bc418528d3b866409064b2746b0793a6c812e23827fbcecbb4444089de5374
font_02_sfnt_off0000fdeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1