Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3bf06f3f59990c0…

MALICIOUS

PDF

76.7 KB Created: 2021-06-23 23:46:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: abdb26c47c14bc611489369315dad852 SHA-1: bb5c27ccb03b43bb5740ff9f7a203d7a4fe16920 SHA-256: d3bf06f3f59990c04ad954ed14077cf5e37f395ba4549cbbe8fd9454707ac948
164 Risk Score

Malware Insights

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

The PDF file is detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains a link farm pointing to compromised WordPress sites, suggesting an attempt to distribute further malicious content. The document body, though heavily obfuscated, contains metadata related to wkhtmltopdf, and the presence of numerous URLs indicates a lure to download a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/jplppsti9rsn49s6deo6b7kap4/femojafobotoxemitu.pdf In PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a1dabbb6c19---31316086860.pdfIn PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb1fb39f03a---51169016365.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609954fbd3ce6---bokaluk.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609c0853c973c---metuzerelu.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7563651ea---vezirizobefij.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/bfb699dbba09dc989046924067ca12dd/riwupusekukowutego.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160743578f2b76---99471388101.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/towewamojojul.pdfIn PDF document text
    • https://capital-tic.com/upload/ckfinder_temp/files/20210603221132.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/bafevirid.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160c10b931fd18---51321614423.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160893556ce2de---70530319552.pdfIn PDF document text
    • https://www.indoorclub-informa.com/boletines/img/file/592512530.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/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=general+banking+questions+and+answersPDF 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_off0000ed7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED7D 5448 bytes
SHA-256: 54a08a659fceb653501ed8397c62d4c547b4f17d6fc452c8093cf1c3ab600f3d
font_01_sfnt_off00010015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10015 11144 bytes
SHA-256: 9e3206a0e0b5468eff8626091b3b97aac1edaa60d4cb6978e8bf4c137e08cbb6