Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f52c9e9226071d5…

MALICIOUS

PDF

76.9 KB Created: 2021-05-31 00:03:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: c5e295664d999631073723bf8efffe60 SHA-1: d9664e3d1ac3e1f5c0211c4ba36e434b2e8625fa SHA-256: 4f52c9e9226071d5a4d985d956539206d35df3891fa9881efa17a7e9915f9d38
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://leonvi.ru/strik?utm_term=oraciones+con+frase+adverbial+ejemplos PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4384839/normal_60561668ad817.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449605/normal_600add7e716c8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374185/normal_606bc10598b79.pdfIn PDF document text
    • https://zegilaritapedu.weebly.com/uploads/1/3/1/4/131438092/6820943.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387056/normal_600dc59170793.pdfIn PDF document text
    • https://dijozimix.weebly.com/uploads/1/3/7/5/137506243/gipekog_devemu_maxakalafo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467043/normal_6015c88ccf4f4.pdfIn PDF document text
    • https://dilaxala.weebly.com/uploads/1/3/4/8/134865885/29df9dae528ddc.pdfIn PDF document text
    • https://xoluvujotu.weebly.com/uploads/1/3/1/0/131070376/lerabojukuwaxikivip.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4365560/normal_5fc95a502a410.pdfIn PDF document text
    • https://wagebesalumiral.weebly.com/uploads/1/3/4/8/134846814/sipozij.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4411944/normal_5fedf1ad3f4a9.pdfIn PDF document text
    • https://fowifosefudewak.weebly.com/uploads/1/3/4/6/134699900/56c579975dfc18.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426687/normal_604a2fbde5d63.pdfIn PDF document text
    • https://vasabofilusav.weebly.com/uploads/1/3/4/5/134585229/d849dfd0bf.pdfIn PDF document text
    • https://wivaxuzavegisi.weebly.com/uploads/1/3/4/7/134769578/8593428.pdfIn PDF document text
    • https://zugatesek.weebly.com/uploads/1/3/6/0/136082504/pavipemekixafi-gaxotixavolanu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379230/normal_600cb8ce16755.pdfIn PDF document text
    • https://xegiduburap.weebly.com/uploads/1/3/5/2/135294675/6718665.pdfIn PDF document text
    • https://dukezowe.weebly.com/uploads/1/3/4/6/134602160/8670909.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496372/normal_6042ed6d6d654.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402718/normal_6002b673b5d7e.pdfIn PDF document text
    • https://nulebuset.weebly.com/uploads/1/3/1/4/131411431/mipomavij.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4E 5604 bytes
SHA-256: fcb77694bdb7d665cc28c14061a1527a9dd6dc7760195a1599e15e5c84581be6
font_01_sfnt_off0000ff4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF4A 11804 bytes
SHA-256: 0f88048480ebcbeee9408288089e9132ab433e8baf2aa73c698ccf97dbdfc554