Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad18f69756de2f4e…

MALICIOUS

PDF

78.7 KB Created: 2021-04-25 00:42:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 4b5ed0bea47c8fe5ff2a56bd6e4c34c9 SHA-1: 5c698fbb741cd9322c996a2d9bac4b23a69d212d SHA-256: ad18f69756de2f4e2cabda81c7e848b8e39226bdece20bcaa7dce309d9cd9303
244 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, many pointing to disposable hosting services and exhibiting characteristics of a link farm. One critical heuristic identified a link to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution via these links.

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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://dafemum.ru/strik?utm_term=good+riddance+ukulele+strumming+pattern In PDF document text
    • https://rapofureduf.weebly.com/uploads/1/3/1/1/131164295/9667d0.pdfIn PDF document text
    • http://carinsusa.info/spectrum_math_workbook_grade_8_free92cvz.pdfIn PDF document text
    • http://dvertsoff.ru/download_new_school_chemistry_textbook_for_senior_secondary_school88xlk.pdfIn PDF document text
    • http://astrology-personal.online/tp_link_extender_tl-wa850re_instructionsaim90.pdfIn PDF document text
    • https://riluvozig.weebly.com/uploads/1/3/4/3/134380056/5120922.pdfIn PDF document text
    • https://webesamogamafi.weebly.com/uploads/1/3/4/0/134012635/bozum.pdfIn PDF document text
    • http://moxolesapudeli.22web.org/kovova.pdfIn PDF document text
    • https://daxozeke.weebly.com/uploads/1/3/4/3/134322415/rinexukiwedi.pdfIn PDF document text
    • https://pinukozemaf.weebly.com/uploads/1/3/4/7/134713375/2a643ae53f.pdfIn PDF document text
    • https://vigobekopu.weebly.com/uploads/1/3/2/3/132302998/547063.pdfIn PDF document text
    • https://goxapixexaze.weebly.com/uploads/1/3/1/6/131607486/kitokotelef_wuvuxalekesir_xidezipameraw_fatosuvebonin.pdfIn PDF document text
    • https://sibetufubexab.weebly.com/uploads/1/3/2/7/132712005/jaxexanabitogozo.pdfIn PDF document text
    • http://merovew.xyz/what_is_the_salary_of_an_interior_designerzezk8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402712/normal_6061c8a8373fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370268/normal_603c1262a7730.pdfIn PDF document text
    • https://davobudo.weebly.com/uploads/1/3/4/4/134432622/ligemagowetikarat.pdfIn PDF document text
    • https://rosunitekuw.weebly.com/uploads/1/3/1/3/131384708/dudatuzifafixu.pdfIn PDF document text
    • https://nugukijozagesek.weebly.com/uploads/1/3/0/7/130739433/debcecdd196df8b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://lewamomad.epizy.com/handy_stitch_instruction_manual.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_off0000f0ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EE 5488 bytes
SHA-256: 002678e629c6abe325077cfd2fa47ee900014492c3b232645318836bac4822da
font_01_sfnt_off00010389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10389 12516 bytes
SHA-256: ebbff2e9eb2dce34f0550313418b28f30dbfb54cfa68442430229d9c407cb9d4