Malicious PDF — malware analysis report

Static analysis result for SHA-256 87ad7a66103316f7…

MALICIOUS

PDF

75.8 KB Created: 2021-06-01 09:52:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 6c40a7d636e6b899fc3600a690364d16 SHA-1: e55a59ff324f4a7f603b5ee91b00dc7ccf3d7d28 SHA-256: 87ad7a66103316f715f4685a916c7aa74a56ebb42d7b2f158bc71e7c5b626cba
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of a malicious document, potentially leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://smidgel.ru/pbw?utm_term=comparative+and+superlative+adjectives+esl+worksheet PDF link annotation
    • https://vikuxujawud.weebly.com/uploads/1/3/4/5/134515409/sujotixerorakaledi.pdfIn PDF document text
    • https://gafujoneruxuf.weebly.com/uploads/1/3/4/7/134728567/2226379.pdfIn PDF document text
    • https://bogilerilixami.weebly.com/uploads/1/3/5/3/135345361/fopejinon.pdfIn PDF document text
    • https://boziwigezuzes.weebly.com/uploads/1/3/5/9/135984517/bitajajokuwizemumi.pdfIn PDF document text
    • https://lififotepul.weebly.com/uploads/1/3/4/3/134339298/xegupigotalog.pdfIn PDF document text
    • https://rexekimat.weebly.com/uploads/1/3/4/0/134017736/7623578.pdfIn PDF document text
    • https://pivubetipu.weebly.com/uploads/1/3/4/3/134328131/de418f3a.pdfIn PDF document text
    • https://vasaradafivoza.weebly.com/uploads/1/3/6/0/136048391/cbecc5.pdfIn PDF document text
    • https://dujedagopodiku.weebly.com/uploads/1/3/4/5/134580966/d7adbe98619a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4372960/normal_602282e5333d9.pdfIn PDF document text
    • https://wumaluruporemad.weebly.com/uploads/1/3/0/9/130969386/5d28106145dc.pdfIn PDF document text
    • https://betogazubi.weebly.com/uploads/1/3/4/7/134768910/pofiwejatiza.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485578/normal_5febcd6edeaea.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490724/normal_5fec25a8f128e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vatojorisa.pbworks.com/w/file/fetch/144441807/guxozetuge.pdfIn PDF document text
    • http://barumena.pbworks.com/f/what_is_the_order_of_star_wars_books.pdfIn PDF document text
    • http://sizolasipape.pbworks.com/w/file/fetch/144413757/mevetama.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/efef3339-464f-480a-8d76-315bb192a3f3/what_is_the_best_water_softener_salt_for_well_water.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/63338954-5902-4b3e-a0c3-c29d0acdfa66/contact_carl_sagan_reddit.pdfIn PDF document text
    • http://tukufidanega.pbworks.com/f/lanogubolosetugaditivor.pdfIn PDF document text
    • http://jesababa.pbworks.com/f/venn_diagram_questions_and_answers_in_english.pdfIn 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_off0000e936.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE936 5512 bytes
SHA-256: ac551f2ae0712e05a5359d265cd5cbc6007c178723d9a0dade281388ef4fa1ea
font_01_sfnt_off0000fbe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE0 11100 bytes
SHA-256: 7ea316a61722ed07d69c5d8fc46909ca2b65c14795834f158ede47b8fb6f34e4