Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fd99da7c057a341…

MALICIOUS

PDF

72.6 KB Created: 2021-06-19 04:30:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 3aa619912acdf352f66a6c4d38fa125d SHA-1: ae78658dbfc436a159bce69aaa88c7b52636100d SHA-256: 9fd99da7c057a341881850581e10c925d33bb03a46b6469dd8ed58a6f1261c39
196 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

The PDF document contains heuristics indicating it is a link farm and uses a clipboard command execution lure, instructing the user to copy and paste content into a shell. This suggests an attempt to trick the user into executing commands, likely to download and run a secondary payload. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16076f705ce037---fatobadodelexesozadaluliw.pdf In PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/16071e3e26bd85---44835279125.pdfIn PDF document text
    • https://uclerbaklava.com/resources/file/25046113183.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/s6jk84bti31utstpp8cd78mqt4/253061782.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/katc4fo96rc05hh4ah8l8u1d5i/59953557376.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/66539110156.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/kebozixogi.pdfIn PDF document text
    • https://rhdplumbing.com/wp-content/plugins/super-forms/uploads/php/files/f6d40a64542904a8d5855b1df9eb0cd6/kubasiz.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9cf427b56---xuvuxesojusuzopekazi.pdfIn PDF document text
    • https://vashadvokat82.ru/wp-content/plugins/super-forms/uploads/php/files/1d9bb93464c46d76baf51ac368e86917/73356210603.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad966adba92---kidufajefakinegasul.pdfIn PDF document text
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ccf0584ca---60326731605.pdfIn PDF document text
    • http://cartopack.com/Images/file/19489096485.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/0c12ef9c7df4e39a9afbae3ceb831d89/rotunuf.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e77d7e53f---40080011480.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/e16c1529cd43006b053ad4609a1b014f/18810494290.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=msoobe+windows+xpPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e077.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE077 4920 bytes
SHA-256: 4143dae72a34f33fe573995c348d68f343cd0f35b09dd5824885af4628da52f6
font_01_sfnt_off0000f165.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF165 10668 bytes
SHA-256: e5e2bccb0b584074d7951dcb914910e97ac5b65a5ee3d385a29daa3094caf3e1