Malicious PDF — malware analysis report

Static analysis result for SHA-256 d809731518cf8f45…

MALICIOUS

PDF

82.6 KB Created: 2021-04-08 01:16:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: e8b2646d23c63160274a1ef9c88d3a2d SHA-1: e58f017c09f2a02d12535e9eb22830d2a0b28bae SHA-256: d809731518cf8f45fe626feb13fb6dd99497c8314424d071479e0b42171dbcb9
186 Risk Score

Malware Insights

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

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains a significant number of external links, many pointing to disposable hosting, suggesting a link farm or phishing campaign. The presence of 'utm_term=cefsharp+wpf++handler' in one URL indicates a potential lure related to software development or handling. No scripts were extracted, but the PDF structure itself is designed to host numerous external references.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://lozipotod.ru/123?utm_term=cefsharp+wpf++handler PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4376849/normal_60289d04105b4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368996/normal_5fe37a8e22c10.pdfIn PDF document text
    • https://cdn.sqhk.co/vipujitebiki/hQsgjic/48076738546.pdfIn PDF document text
    • https://dufubixapitosig.weebly.com/uploads/1/3/4/5/134503348/26994f91905.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467912/normal_5ffb826a3ecca.pdfIn PDF document text
    • https://cdn.sqhk.co/gegojagakexu/fKhfjcT/34143903359.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452386/normal_6035a4c6e0feb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393193/normal_6026ff6744db6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415291/normal_604196085b44a.pdfIn PDF document text
    • https://xoregofejaba.weebly.com/uploads/1/3/4/6/134651656/jojunasowinigow-zezovomi-xufib.pdfIn PDF document text
    • https://dolojimopa.weebly.com/uploads/1/3/4/8/134887070/6160652.pdfIn PDF document text
    • https://pegiromilu.weebly.com/uploads/1/3/4/6/134683304/3567383.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7e005a1c-fb68-43c1-af83-b854b6a2d282.filesusr.com/ugd/dcfb95_90429ea8acf04563acae4caf57398f3b.pdf?index=trueIn PDF document text
    • https://16cc4848-9a85-487f-bc1d-da55f68f8448.filesusr.com/ugd/dcf86b_73370da76b844be4bf5a159b652d1332.pdf?index=trueIn PDF document text
    • https://36fc1fe3-b646-4cc1-b6e9-de51469aea27.filesusr.com/ugd/3eb4bd_04de3ec801004a0f999d9c3dfe06d4ba.pdf?index=trueIn PDF document text
    • https://5862e4ea-63a6-4c92-af93-e06d02d1a664.filesusr.com/ugd/eaa371_153a9d65c7fb432c85358fbd8306127a.pdf?index=trueIn PDF document text
    • https://ca30e0e0-ecf2-44ab-b6a2-fe26291458be.filesusr.com/ugd/34e21e_d0095baaf11949b5a663ece2c0b7ae35.pdf?index=trueIn PDF document text
    • https://4bc473c2-84d0-4913-8b4e-281bf44fba2e.filesusr.com/ugd/a25dbd_6655307f90f54d129c9a71668498bb50.pdf?index=trueIn PDF document text
    • https://168d2a81-f750-40c6-a653-3787650f980d.filesusr.com/ugd/3bcfef_4bfa61e612b84b89aeefb40cf96ae1c6.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFDA 5484 bytes
SHA-256: d5b8677b25cba414beb7b026f36c3293bf3b1a9a6b42d3d9ecb011a4140d23cd
font_01_sfnt_off000102d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D7 5128 bytes
SHA-256: c6489347864c1ab2a818df1693c841a06e2ea5840615571fadd0b5224c39f59a
font_02_sfnt_off00011455.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11455 11540 bytes
SHA-256: 549ccf385b57fe879bb5636cf91d177c572747c3fdd8d6246311322634d765be