Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0b94f8244228ea0…

MALICIOUS

PDF

74.1 KB Created: 2021-05-27 01:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 28685c6eafe3026e86fe6980152d4096 SHA-1: 3076e4873c7420a1e4d9ea890f5f3873810556ae SHA-256: f0b94f8244228ea09c9c6215f828579dab3f758d0051814236b20e3609d3db0f
116 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised websites, specifically leveraging WordPress upload directories. These links are designed to host and distribute further malicious PDF files, as indicated by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier strongly flags this PDF as malicious, suggesting it's part of a campaign to deliver secondary payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609368c30e495---labowiposemabe.pdf In PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160a394fcba94f---vavijutiruwusawigubidej.pdfIn PDF document text
    • https://kvkumariajnkvv.org/singhania/downloads/file/ziwufuf.pdfIn PDF document text
    • http://anandamsanyal.com/userfiles/file/98749025299.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2eb195cdc---30174258203.pdfIn PDF document text
    • https://tecnicadovolante.com/images/file/11711128304.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/16070bef0527e8---burotasununuvir.pdfIn PDF document text
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/c1fceb7d912bbbc6276c0389788eb3bd/85877431795.pdfIn PDF document text
    • http://www.thaiboat.net/image/upload/File/71613465978.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/a1a0d6f9c880f4b476f53aed57029737/navudorakigusexufenup.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/160a3389a959e8---sefuzewir.pdfPDF link annotation
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/7b00e5e8f601874adde34be85954e613/57606675647.pdfIn PDF document text
    • https://bladmedyczny24.pl/wp-content/plugins/super-forms/uploads/php/files/dffa2be3c43ada6c1552634e7ee83f6c/51406877019.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4610036e6---58543704849.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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=exercice+math+statistique+terminale+bac+proPDF 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_off0000e08c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE08C 5464 bytes
SHA-256: 452e00707c9dcee5d7dc9c06af996f8f959596c2dd5cb4806892ef7462c50f26
font_01_sfnt_off0000f2fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FB 12936 bytes
SHA-256: ae7d76a2ff7d823896b7c4cbe4af4f35e9a9bb1bb3420efc37c8f482d54024be