Malicious PDF — malware analysis report

Static analysis result for SHA-256 434e1eb58f2155c1…

MALICIOUS

PDF

80.0 KB Created: 2021-05-29 08:42:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 4e105c6148622b32c530a141d6e33033 SHA-1: b65db4a741d04a92485c234da227240f5690b199 SHA-256: 434e1eb58f2155c11906b57c767d049ea8d8557f3d14b00e1e4d7f916fbf982f
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 0.9995

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://golowaki.ru/strik?utm_term=java+developer+interview+questions+for+experience PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4448540/normal_601b3acfb43be.pdfIn PDF document text
    • https://wezoduvum.weebly.com/uploads/1/3/4/0/134096245/4280226.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444378/normal_603ab4c20718a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464878/normal_5fe6173767f60.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405179/normal_602746558873f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454973/normal_5fec9974a8930.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490725/normal_5fefed2543faf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415322/normal_6017486416bb0.pdfIn PDF document text
    • https://figeneluniw.weebly.com/uploads/1/3/4/8/134857588/318e42.pdfIn PDF document text
    • https://xatuguje.weebly.com/uploads/1/3/1/8/131856293/nalal.pdfIn PDF document text
    • https://figiroxofidun.weebly.com/uploads/1/3/0/7/130740151/lerida_roliw.pdfIn PDF document text
    • https://kuvuwivozud.weebly.com/uploads/1/3/6/0/136091804/9d811a14c52.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470038/normal_604d62f40f17a.pdfIn PDF document text
    • https://pufujodixig.weebly.com/uploads/1/3/1/4/131438007/bifade-nadepusij.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375890/normal_5fd3223fa5177.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451208/normal_605f2dfd571ae.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383702/normal_5fe1706e6bc18.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417643/normal_60283ded5aa97.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/3714429d-a723-4f94-9a07-14af9dc1ca02/31959486430.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ab6424d-9cd6-4bee-96f6-d4c3e8cef630/biddeford_electric_blanket_warranty_registration.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f6efc786-5087-47e0-b961-35fbf6e27d2f/jukotupavip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/450f4fc0-5def-4d4f-bdc2-293671ba2ca8/noduwofiwi.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB78 5364 bytes
SHA-256: ab57633c769d60af8e559751a1d6c26805d5a6be6e7ac9b1378ca8ad03ed2cad
font_01_sfnt_off0000fddb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDB 11128 bytes
SHA-256: 27860940bf93324a918b1bed8c70e8b117f8c04cd5cd5ae6a0733ba6b1c2d593
font_02_sfnt_off000123a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123A7 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176