Malicious PDF — malware analysis report

Static analysis result for SHA-256 aec7a3e553a30414…

MALICIOUS

PDF

70.0 KB Created: 2021-05-04 17:13:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: 6584da2d88ad093d8066b4e1e1ae4072 SHA-1: 5d166d0a8b02691287bc18f957c64be1303556ce SHA-256: aec7a3e553a30414ba6e4b346eb9461bae80308ff8012849e51cb5fcc9a65f66
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The embedded URLs are likely part of this distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5b6b08487---92967778220.pdf In PDF document text
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/7e4ecde2729d1cf451da5a91896d9158/pozumegijiwewubawin.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072f68262f23---88826034775.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/677cb0004516231f5841a2a9ea15eb03/pavevewixapuweripo.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6903e3247---13327133452.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/4493bc5c67a695370ad7870e7855b3f9/saxutebaxurologosizolo.pdfIn PDF document text
    • http://hillcountryawningsandsunscreens.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eed483612d---zisivopabafoj.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca3da77d29---52359878388.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083362aae5fc---nitufusuxutajumatizug.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16085861a7a5f5---51603855616.pdfIn PDF document text
    • http://adria-ex.com/images/blog//file/97707057449.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/6cf94d14942c97e445bab0537502c71f/gidixidod.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/149c6dbc65989adb5a0d96a063ad8281/divakusudokezogurijo.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607ef3a339d68---tigujekevodofax.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608d5495cc540---pedafowepuseruk.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/PmAiG5ZyT-k/uplcv?utm_term=lol+surprise+sheet+cakePDF 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_off0000d658.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD658 5028 bytes
SHA-256: efd286de79a1cf812dcf8fe27126d92c64244619a5f392f45b17fa4da1b51d27
font_01_sfnt_off0000e76d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76D 10708 bytes
SHA-256: c25dc98208830bb08e570d4ce90f9694e17b8fafd799dcbf4b230d73ff975682