Malicious PDF — malware analysis report

Static analysis result for SHA-256 dec955a2c2973da4…

MALICIOUS

PDF

91.5 KB Created: 2021-06-03 15:57:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 7db2e5469302943e6d55c23cfd2c98d3 SHA-1: 1195bc2fb8b80def2c111832bd82c03541ee881d SHA-256: dec955a2c2973da4766a02c8e3d2f7eb740ed5bea934e55d0dac75532f6ea797
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://medvor.ru/pbw?utm_term=solving+systems+by+graphing+and+substitution+calculator PDF link annotation
    • https://boxomuti.weebly.com/uploads/1/3/4/0/134016719/nanebax_dejanevizuv_lerux_sovaxa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393486/normal_5fd99ed1ad52b.pdfIn PDF document text
    • https://nomumiti.weebly.com/uploads/1/3/4/3/134330837/8508661.pdfIn PDF document text
    • https://jejonogukoji.weebly.com/uploads/1/3/4/8/134864124/mawulabenonezo-bibigotunajavo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481409/normal_5fe6410f437ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415543/normal_5feaf1b3d88b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393628/normal_60461150d110a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4475727/normal_5fcb9ba437f32.pdfIn PDF document text
    • https://tamoniwezetiro.weebly.com/uploads/1/3/5/9/135961995/vuledejuropalipadagu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382201/normal_5ffac0533a2b8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384307/normal_6037e3cea8754.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482405/normal_5ffe12c743640.pdfIn PDF document text
    • https://zegepami.weebly.com/uploads/1/3/0/8/130874110/1285029.pdfIn PDF document text
    • https://ximesadi.weebly.com/uploads/1/3/0/9/130969353/zokuzovuxobogok.pdfIn PDF document text
    • https://fufobulevuzim.weebly.com/uploads/1/3/4/6/134650144/d50f4d.pdfIn PDF document text
    • https://sewidilegewe.weebly.com/uploads/1/3/4/8/134883142/e422c89.pdfIn PDF document text
    • https://vobilazi.weebly.com/uploads/1/3/5/3/135300702/b3effebe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417025/normal_600cf2d6bfc43.pdfIn PDF document text
    • https://musegozaxugovu.weebly.com/uploads/1/3/0/8/130873783/fukisi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380382/normal_602db10469620.pdfIn PDF document text
    • https://navanelesud.weebly.com/uploads/1/3/0/9/130969746/1405155.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4386839/normal_5fde0a68c2d1e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408471/normal_60510b4f0e7dc.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010b62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B62 5892 bytes
SHA-256: 3f78fafc96c6d1a259117959ced959df9809a256d9b4aa526c41acc3a68c609b
font_01_sfnt_off00011f48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F48 12240 bytes
SHA-256: 043625dcd6065b2bf5ea269be2c99ea9af757bf15ab1d98eee42afeb92ae1a3e
font_02_sfnt_off000148fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148FE 16060 bytes
SHA-256: b10e7a0583bf6b216a5471aeed10f14210f1dda3adb60ac5169fcb38ba12e60c