Malicious PDF — malware analysis report

Static analysis result for SHA-256 0e8b17ec729c85d8…

MALICIOUS

PDF

76.9 KB Created: 2021-06-15 12:23:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 187554f9904baa2e3393acb1744e3763 SHA-1: 66917b3f36cdded03b40f426028465c4d32ab65b SHA-256: 0e8b17ec729c85d888358f97523954c268ebe50b57e183be19911853612f4452
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm or SEO spamming operation. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of malicious activity, potentially leveraging embedded JavaScript for redirection or exploitation.

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
  • 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://archism.ru/pbw?utm_term=ruby+english+translation+book+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4481663/normal_600d6f2e9a923.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4461232/normal_60b5af701795a.pdfIn PDF document text
    • https://rajukoxo.weebly.com/uploads/1/3/4/5/134508115/5067306.pdfIn PDF document text
    • https://sizegetode.weebly.com/uploads/1/3/4/3/134309939/481464a7ea8.pdfIn PDF document text
    • https://xowedoditigivi.weebly.com/uploads/1/3/4/7/134714126/9fb3e56.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4374517/normal_60b71e24166cf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366309/normal_6055a0429d76b.pdfIn PDF document text
    • https://lamobivuletopuk.weebly.com/uploads/1/3/4/8/134863798/987173.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376354/normal_6043044c90f55.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476566/normal_601fc2123dc20.pdfIn PDF document text
    • https://nizegefubazada.weebly.com/uploads/1/3/4/8/134872151/8041333.pdfIn PDF document text
    • https://nawolokiwepona.weebly.com/uploads/1/3/2/8/132814855/9270653.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495387/normal_60496b51dc4a9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4528915/normal_604d5c647d9f8.pdfIn PDF document text
    • https://bosonelete.weebly.com/uploads/1/3/0/8/130873804/d5c42234b490.pdfIn PDF document text
    • https://finibolamojirum.weebly.com/uploads/1/3/5/3/135341575/e6d53698c241d60.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kimotamiju.pbworks.com/w/file/fetch/144512664/how_to_create_a_branch_in_github_repo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/246edc76-6ef0-4cda-98be-8b60de6990bb/8610066269.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ceca6f56-e533-47e1-a875-f19dce02a136/sath_nibhana_sathiya_watch_online.pdfIn PDF document text
    • http://punuxawuva.pbworks.com/w/file/fetch/145315509/gta_v_cannibal_camp_location.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_off0000efbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBC 5616 bytes
SHA-256: 21ee39c7405d65dbfdea92f6d5544a03d32751e5f02b2d5527eb2576cb0595c1
font_01_sfnt_off000102e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E0 10340 bytes
SHA-256: ef0c298e981e6015ed320f29fceef66877e43bce35dad9ba97dee2c8caa62fbd