Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8d11e91eb36175b…

MALICIOUS

PDF

79.9 KB Created: 2021-09-13 07:14:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6a4fc91707a18f98176eeaa11f3e13a4 SHA-1: 3753d31b8f065dc0406d4d9371640f3e86d29e45 SHA-256: d8d11e91eb36175b3f888517f7c90bbb457d0def1631d3eb9e013fd2a878423d
156 Risk Score

Malware Insights

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

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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 http://billsky.ee/files/file/vagaratonisofudo.pdf In PDF document text
    • https://economiadecomunion.net/ckfinder/userfiles/files/gizuzobibikakosu.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137132c25ec7---jabaxozovutofexuj.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c2bb6d89b1---vezofesuwuxasiwen.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/56037343307.pdfIn PDF document text
    • http://hoadondientu-ptp.vn/images/ckeditor/files/gopaniwegujikodotolabebop.pdfIn PDF document text
    • https://opsclown.it/ckfinder/userfiles/files/dewudawudub.pdfIn PDF document text
    • https://rkdestate.com/userfiles/file/sigewuret.pdfIn PDF document text
    • https://smartmedia.ro/app/webroot/files/userfiles/files/3138167322.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec097482fb---lapusodadu.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/6277ab6451d720f9a669f91764d41baf/47869007059.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/44562672652.pdfIn PDF document text
    • http://dtjxbpzx.com/filespath/files/20210901130858.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/6276447601.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1f904dfbc---80200270318.pdfIn PDF document text
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/punerogewekasoji.pdfIn PDF document text
    • http://bobmeetin.com/media/galleries/files/87367129987.pdfIn PDF document text
    • https://drjou-vc.com/upload/files/padugujofiwexabuduze.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/90370209283.pdfIn PDF document text
    • https://reparation-mobile.net/userfiles/file/55833719660.pdfIn PDF document text
    • https://goldenlinejsc.com/userfiles/file/81344055375.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210904060525.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/tumapuzimatibuxoze.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/8554ce1a3ea937639a14bd4f31fcb1cf/puvaliber.pdfIn PDF document text
    • http://yey.uw52.com/upload/files/movuludogizamufikopaka.pdfIn PDF document text
    • https://mar3ol.com/Files/files/sazofulokijogepo.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/6ee293a1b3a7a94f36d4003270a5f96b/81187336219.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=car+simulator+2+apk+modPDF 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_off0000d4cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CC 17092 bytes
SHA-256: 513324a2bc0bcbaf62420c7bc54bba85549d62339dc38833e07ef93858080ed8
font_01_sfnt_off00010113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10113 10660 bytes
SHA-256: cc78740cdcc6bad4ffb2fcb20398710ed329cb4c035307fe5f1a660792b2d0b9
font_02_sfnt_off00011996.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11996 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1