Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0f5ce6c1f8c850…

MALICIOUS

PDF

93.9 KB Created: 2021-06-15 10:14:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 091881c87e64032883d96c0d8a52df9d SHA-1: 39775437d3a4fdfbf18b28a2479f0568b44bd76b SHA-256: cf0f5ce6c1f8c850933e7323a3cb77563a79b53f1402ffd137faf0a5fe1e254e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://drafthe.ru/uplcv?utm_term=tni+mp+application+answers PDF link annotation
    • http://humanitool.ru/userfiles/file/gobotasafesiwavubiwaz.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/235e29490507cf5d7b708cbe0dacc81c/zarasige.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1606d35fa2ee0e---tefifanuzalidat.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/10646593873.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d3d911d72c---16354174080.pdfIn PDF document text
    • https://gamaconsultores.cl/upload/file/gufomed.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/f8f0bb89f01b5e90a89c5fe61f202848/segodala.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/8d73f4c5a9445666af4e64775f121914/61414246686.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/vepasuveroxim.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082ac9f81f6d---varijinuxadonodozukunev.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/sccsdgtvt87vigdp0chmg3nie6/nukibakodojazuv.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/2538481482eb47b3d99c0b8b94df1041/67668074548.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/gazosijolikuliwokob.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f41175cc6a---gizuvojaw.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn 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://scripts.sil.org/OFLIn PDF document text
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001089d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1089D 5724 bytes
SHA-256: c1a90dfd09dc0f742abf83ef8b9bbbc0c9bb33321115df6aae4872602a298e34
font_01_sfnt_off00011c3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C3A 5120 bytes
SHA-256: 4bc1e1501f2046621e1decefecf0e9124c2b07e20d3e4b9ec328d67492865e32
font_02_sfnt_off00012d91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D91 7764 bytes
SHA-256: de08784d5374697cd7a76d0fee4c89e9280664b53d7b23aa0b39144f622f6148
font_03_sfnt_off00014311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14311 11972 bytes
SHA-256: 0798630a7f174ac96fe25fa2cb559cab28a357065d0f850178fc6561d6d57dc7