Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9f6fbda422897af…

MALICIOUS

PDF

79.2 KB Created: 2021-09-05 22:01:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 849f82b4a4b69a7e2149f298fd93d39d SHA-1: 77731c14e2c9768b64d65c1938ea69cbfd962313 SHA-256: f9f6fbda422897af1d63edf12069fca943ab541367cb5b402a9ff04ba5f41d91
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Numerous external URLs were extracted, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The PDF structure and embedded content are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=linux+mint+cheat+sheet+pdf PDF link annotation
    • https://sammycar.ch/sammy/sites/default/sammyfiles/newsletterfile/tetiripezabasulisatiset.pdfIn PDF document text
    • https://kvkumariajnkvv.org/singhania/downloads/file/ganewamami.pdfIn PDF document text
    • http://chongthamphucthang.com/images/news/files/woluze.pdfIn PDF document text
    • http://arlingtonhigh1961.com/clients/e/ef/ef36f0800c0a5d5a0b00d5ecc8c3c6da/File/zaxoluko.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/77321771804.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/86404842632.pdfIn PDF document text
    • https://lanhcongnghiepthinhphat.com/upload/files/gamafalasuzava.pdfIn PDF document text
    • http://etabetasurvey.com/userfiles/files/jabejitupulewiwopu.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bd3156be4f---513652619.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/n3cpsd5c4ofh99tr5f6j4o57mt/514790160.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16134385ebd813---rejowu.pdfIn PDF document text
    • https://pet-fashion.ro/mm/file/popugilubozinitulezonuvo.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/wosozovedotavikewan.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/95d052b6df7c4411518cf03bbe232197/sitog.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/7023f4bcd247c33d958c604925c1ff5e/5466652316.pdfIn PDF document text
    • http://avatars.ru/userfiles/file/vupawafezemekanuvef.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160934189c1e00---balejusogegaluri.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/vigofafanaruvaludowudirok.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/19010772789.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/maxikezeno.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/32282910200.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/mujina.pdfIn PDF document text
    • https://lamaisonducoeur.ca/upload/editor/file/xolixovorirujer.pdfIn PDF document text
    • http://blfimmobiliare.com/userfiles/files/67234696008.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_off0000ce65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE65 10776 bytes
SHA-256: 6c7d6300c2158e93b636360167b720c2e9bc688beeb5313696e828c7255da653
font_01_sfnt_off0000e708.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE708 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF1A 18276 bytes
SHA-256: 53018ece35dee291e2124215d39e763bd7edd8a1549823d706b2f1bb00b30321