Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa5fd25d706a648f…

MALICIOUS

PDF

91.6 KB Created: 2021-04-30 10:21:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: f18675ac10cdfe25c9c766a30aecda35 SHA-1: 2074a152b49abaf20364a11c1ac23c8d069fde03 SHA-256: aa5fd25d706a648fdd847378d7d7dcc7af397270a1cfbb5a00efbf7b661b8859
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to redirect users to potentially malicious content. No scripts were extracted, but the structure and URL distribution are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.axelendinggroup.com/wp-content/plugins/super-forms/uploads/php/files/2d9aa391fd49ab123cad97561f001a37/90463672070.pdf In PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/d405da4c1db6282cd14374ab81a04604/renatoxesafal.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a6ad7b58be---vozarok.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d7b8fdee4f---donotomiginele.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16078101bef615---betimim.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/4c14f959a2855291d8ec4ce3e8507f5f/18979447343.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1eebe8638---likibawurisupez.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607087622d249---64075816704.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcf33d589f---94281375287.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608912f04fdfd---nolije.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2866e7f49---53836097165.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e16b3b36ab---74936897160.pdfIn PDF document text
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/7d2f11ec2f9573fa13a56550ce74680e/wezuvafipavaparike.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/od71kv8j00rp6cj8rk7cof8cqu/bezesodepabalibepuwevalib.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16070cc6a16959---89396393160.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=shape+form+or+fashionPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000119f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119F9 5212 bytes
SHA-256: e86c6cdbbfb9541b67419acecea704d454ee88568652b8ee9b5eba510dc31718
font_01_sfnt_off00012b84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B84 2112 bytes
SHA-256: ee8ace99f159619128a0f88bd6f86bb73ffe6d54543f10bb18a80ba861f6a7fb
font_02_sfnt_off00013555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13555 12516 bytes
SHA-256: cecbcf9a9fa955692de3808fc372d083e82250a56c9522349f56866269084197