Malicious PDF — malware analysis report

Static analysis result for SHA-256 6efb88116ffdfe68…

MALICIOUS

PDF

68.0 KB Created: 2020-11-20 17:11:44 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 487ec86b8644f926e266b3565db01b75 SHA-1: dbde4ab7e1e85dc973737ff7847f225bfda28fa1 SHA-256: 6efb88116ffdfe68da591c51515a5bad89f534aa92e0cf0e871c3d34974f4f9c
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, many pointing to PDF files, suggesting a link farm or a method to distribute further malicious content. The document body, though heavily obfuscated, contains text related to '100 games unblocked' and the authoring application 'wkhtmltopdf', indicating a lure to a potentially malicious website.

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://trafffi.ru/123?utm_term=100+games+unblocked
    • https://cdn-cms.f-static.net/uploads/4374359/normal_5f9438ef7432e.pdf
    • https://cdn-cms.f-static.net/uploads/4389582/normal_5fa05380646a5.pdf
    • https://rebolotor.weebly.com/uploads/1/3/4/3/134364816/9453185.pdf
    • https://cdn-cms.f-static.net/uploads/4425227/normal_5fad8838edba7.pdf
    • https://vidojibirulon.weebly.com/uploads/1/3/1/0/131070792/ganeb.pdf
    • https://cdn-cms.f-static.net/uploads/4379379/normal_5f9c61e59f1a8.pdf
    • https://jarapitoxedomel.weebly.com/uploads/1/3/1/4/131437170/1504841.pdf
    • https://terarawuterojuz.weebly.com/uploads/1/3/0/7/130739827/vebaxodimigop.pdf
    • https://punotajevi.weebly.com/uploads/1/3/4/2/134266109/a7de153e660.pdf
    • https://rimesozarabef.weebly.com/uploads/1/3/1/6/131607712/tabutekes_mekiwodeguliva_dasatakikenit_vedatebodameju.pdf
    • https://cdn-cms.f-static.net/uploads/4474989/normal_5fa6a1fd96e97.pdf
    • https://belafawejogawol.weebly.com/uploads/1/3/4/5/134583754/jakadaworulozazur.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/zebarufuridorur/dasuwe.pdf
    • https://s3.amazonaws.com/subud/al_quran_word_by_word_translation.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_off0000cc4f.bin
430d91eb9409fdbc3bf4c99c0b3ab0928907de3a06ed4b4c67a34fadc4507e8e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC4F 5468 bytes
font_01_sfnt_off0000ded8.bin
3355ee9061d4d9a9a2578ede968be10d4e97f68ea51c91d2612afd4a70120032
pdf-font-stream PDF embedded font (sfnt) at offset 0xDED8 10776 bytes