Malicious PDF — malware analysis report

Static analysis result for SHA-256 11c76ca4f51445a2…

MALICIOUS

PDF

74.2 KB Created: 2020-12-26 18:41:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 785287dca0e01af066167ea0b327e563 SHA-1: 1a5158ecaa83f622147f7a59dd195e2710a630ef SHA-256: 11c76ca4f51445a23bf5a8995a9dae8b805eec1ff549d85f4043db2042b4288f
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by multiple heuristics, including ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of a large number of external links, including the primary URL https://trafftec.ru/strik?utm_term=pencil+case+pouch, suggests this document is part of a link farm or phishing campaign. No scripts were extracted, but the PDF structure and numerous external links point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://trafftec.ru/strik?utm_term=pencil+case+pouch
    • https://cdn-cms.f-static.net/uploads/4377380/normal_5f8ad1e65a0dd.pdf
    • https://jonipafatanepa.weebly.com/uploads/1/3/2/7/132741476/kudusajovosabevo.pdf
    • https://cdn.sqhk.co/kezixowog/T7m1dHP/burger_king_2563.pdf
    • https://cdn-cms.f-static.net/uploads/4463812/normal_5fdb7a860d31c.pdf
    • https://cdn-cms.f-static.net/uploads/4492871/normal_5fbed6ba583ce.pdf
    • https://cdn-cms.f-static.net/uploads/4461744/normal_5fa2147313b07.pdf
    • https://lifagixuwemup.weebly.com/uploads/1/3/0/9/130969738/mosufav-rumosiba-vonuwifeji.pdf
    • https://gikusevenax.weebly.com/uploads/1/3/4/5/134529244/wofiwi.pdf
    • https://cdn-cms.f-static.net/uploads/4366367/normal_5f9af20028522.pdf
    • https://kelutatu.weebly.com/uploads/1/3/4/5/134521402/susanofazojo-xumufewova-vasigokepanit.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/d09e5aa6-8f1b-4dae-9d25-65c4a91f08bb/11925967225.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6c2.bin
bf8318be893249939ae297998a451e61d21787c2500ea2304593363b835503b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C2 4928 bytes
font_01_sfnt_off0000f788.bin
535c030406c075aafabc8b97d6e4326327835a166556b1705cbadce2ac6d99f8
pdf-font-stream PDF embedded font (sfnt) at offset 0xF788 10880 bytes