Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c99190e22059532…

MALICIOUS

PDF

85.4 KB Created: 2021-09-01 17:25:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 95a7bf9e2fff2042d35153eafb71c825 SHA-1: 5b76b3512f715a453be35e644d23d39fb35af854 SHA-256: 8c99190e220595325ae70d966ae9bfa0463cf2c74ce76bad16f32278cc84dfae
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable, so the rationale is based on the PDF structure and URL analysis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/k5apnqake13iad9ngabpo25jvg/guzukadozi.pdf In PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160bef5ddee9bb---32973564673.pdfIn PDF document text
    • https://didacostruzioni.it/userfiles/file/22641204323.pdfIn PDF document text
    • https://palet-school.com/files/files/pizumutigixovanepimiwij.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160972b4c6157a---gavida.pdfIn PDF document text
    • http://daimarconstrucciones.com/images/admin/file/wizinodinaneposi.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/fe6b63db5956a9a04b7cb09d9242b118/nuvinesososujajosa.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/pujijusojowitaperaz.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/kuxajesatemajavelowupag.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/97199388115.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/25844412361.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210607_DF7995F9D2C0DDD8.pdfIn PDF document text
    • https://homeuu.biz/upload/ckeditor/pages/files/zewove.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c24b14bcf---vovemaxed.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/5ab419acdc67f8c02a4b60ea88ac9683/pizozofup.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/7a7ad292808faf0c961edc4edd900d5e/73850916124.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/83601468797.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/16070a29b52293---4271269374.pdfIn PDF document text
    • https://sofupingame.com/calisma2/files/uploads/vefumufe.pdfIn PDF document text
    • https://www.marjojaspers.nl/ckfinder/userfiles/files/rigepuzawovo.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/6426012610.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+get+a+p60+from+a+previous+employerPDF 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_off0000e85a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE85A 11244 bytes
SHA-256: d29b9f7da576ff6f231530b17b996826cce38dee2f6f837f7fbcb32be8026643
font_01_sfnt_off000102d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ae9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE9 17540 bytes
SHA-256: 57e3a47f099f741fe32a1356da6ec8357e88dc0646c6f346c7a611a48d28bfe5