Malicious PDF — malware analysis report

Static analysis result for SHA-256 13260518a62750b6…

MALICIOUS

PDF

77.0 KB Created: 2021-09-01 11:26:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: bc34ed2382f14861010462ad9f795ef4 SHA-1: a10d1ae263477d88be665f70d27cb76d6eccb9a3 SHA-256: 13260518a62750b60f677417db806a88093f9297cc2563bb27844e8486b7b1bc
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users. ClamAV and ML classifiers strongly indicate maliciousness, with the primary attack pattern being a lure to external, potentially malicious, websites. No scripts were extracted, but the structure and URL analysis suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://przedszkolenisko.pl/userfiles/file/34148960155.pdf In PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0f2379d9f---13511174432.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160900e0dc08a3---51585337877.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/retigawujevafejefuf.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/toxebalofadozologexa.pdfIn PDF document text
    • https://dlt-nkp.com/fileupload/file/bewututofuduzamu.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/88104122743.pdfIn PDF document text
    • https://xn--80apefbdm9ah5g.xn--p1ai/userfiles/lukofuvojewewosegenepepe.pdfIn PDF document text
    • http://bendhigh1970.com/clients/1/10/106e6567aa8bd3cecf4080670b11bd10/File/397710394.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/robusoxixumoxenoxuluvon.pdfIn PDF document text
    • http://goldsunjsc.com/upload/files/diwemer.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/jaxisofenabatutiguseno.pdfIn PDF document text
    • https://indacphuc.com/wp-content/plugins/super-forms/uploads/php/files/9k8ffgvi8crta0osn5f0c43uhg/17233320659.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/53730348198.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/ab1ce29ef932b6f5c275a2407de60b6b/savaxonerit.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1611fa7b5da689---62174453386.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/lomojefotuvam.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/e4lvf0vlrqvs89capqkbopa517/53915535087.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=the+film+unhingedPDF 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_off0000d016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD016 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e82d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE82D 10216 bytes
SHA-256: f3bdf00f8f9774cf96fb1a09b5b89d2d057e10e84cdaf09e89da7d3b7aa64b2b
font_02_sfnt_off0000fe8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8B 16272 bytes
SHA-256: 7f52326939b77634c9eef99c6198ba44e1b370f457aedd1ab6da065f0c2480cf