Malicious PDF — malware analysis report

Static analysis result for SHA-256 09910a90b62bcd8e…

MALICIOUS

PDF

76.1 KB Created: 2021-06-11 09:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 0f49efc846e9ce256b95abb21c895579 SHA-1: 3ffa809943df35ea4706e430d90d5270562010e4 SHA-256: 09910a90b62bcd8ebfd05db70c1d92131f88b7a85816f29c9aefb2e3683efc42
156 Risk Score

Malware Insights

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

The PDF file is identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. It functions as a link farm, directing users to various compromised WordPress sites and disposable hosting domains, likely to download further malicious content. The document body, though heavily obfuscated, contains references to 'udan medical surgical nursing pdf free download', suggesting a lure for educational material.

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 https://philabc.ru/uplcv?utm_term=udan+medical+surgical+nursing+pdf+free+download PDF link annotation
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/itbspc3t65lkjmkkkgod313qtk/bibokapaxowibive.pdfIn PDF document text
    • https://walkandsmile.com/userfiles/file/rolefejewulavov.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1607ab8efcd4e3---15439120967.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/2fbbe20b9708e43164cddd15c96ce66c/tajixogojogavovele.pdfIn PDF document text
    • https://nepalimodelagency.com/userfiles/file/jupasukawenew.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a85c4662409---79636352852.pdfIn PDF document text
    • http://luvnchrlysenglishtoys.com/clients/861429/File/mujisuw.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/459oh410iia7enjht1peo19hmv/tagewulonikibovufogez.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e17489614f---8238510034.pdfIn PDF document text
    • https://www.vbclighting.com/wp-content/plugins/super-forms/uploads/php/files/e5c609f3bdb008823bc69d4cd060ba69/14945865613.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/bozenifudutigapabe.pdfIn PDF document text
    • http://best-infosystems.com/userfiles/file/69661251402.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac89cae776---31644519917.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16078b6f4c3457---17139089482.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/b9cc66dfad9e660c7847bc4dcfd9718e/93506171220.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/ee12ec4a301c33eabd3a6153a51dce3c/50900559945.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160740ccec5919---8562108274.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/ci4j3a1pii2mbie98aut2nek64/gidibojimonoj.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F8 5556 bytes
SHA-256: afaa45de2d62163822cfea6b9e7fc7794650b3228f0bd5b597a417d1c2b94557
font_01_sfnt_off0000fbdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBDD 11100 bytes
SHA-256: afb1a1210e56b47880182d3033456ea4aa93e5131f3172caf62d7584d1d8c45d