Malicious PDF — malware analysis report

Static analysis result for SHA-256 74d481a1fdddd093…

MALICIOUS

PDF

76.5 KB Created: 2021-06-02 16:17:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7b7f19fe0dd33c71a7840e3bc3b67cc5 SHA-1: de068fcc11ab415d3b6e9250a7161d1588b24580 SHA-256: 74d481a1fdddd093aaa125a10f663cdd6f505445a4f59c5986b605ab0794b1e9
164 Risk Score

Malware Insights

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

The PDF file contains a heuristic firing for an external URI pointing to 'https://crewmak.ru/pbw?utm_term=minecraft+bedrock+edition+download+mac', which is likely a phishing lure. The ML classifier and ClamAV detection strongly indicate maliciousness. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of numerous external links, including one to a PDF file on cdn-cms.f-static.net, points towards a link farm or phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://crewmak.ru/pbw?utm_term=minecraft+bedrock+edition+download+mac
    • https://cdn-cms.f-static.net/uploads/4374518/normal_602f1979df4a5.pdf
    • https://cdn-cms.f-static.net/uploads/4496605/normal_602fff7c88857.pdf
    • https://cdn-cms.f-static.net/uploads/4458827/normal_606cf78ea4d2e.pdf
    • https://static.s123-cdn-static.com/uploads/4403541/normal_5fe02db8c425e.pdf
    • https://static.s123-cdn-static-d.com/uploads/4369514/normal_60b06c9edbb5e.pdf
    • https://cdn-cms.f-static.net/uploads/4379974/normal_606100fb9fb50.pdf
    • https://jaroxifapo.weebly.com/uploads/1/3/1/6/131636664/riletewef.pdf
    • https://cdn-cms.f-static.net/uploads/4455195/normal_604ed2d689108.pdf
    • https://nafesidupige.weebly.com/uploads/1/3/2/6/132680955/bupusokimotig_pagamedorixamu.pdf
    • https://cdn-cms.f-static.net/uploads/4495696/normal_60200348db3f3.pdf
    • https://static.s123-cdn-static.com/uploads/4457881/normal_6000f261b4de6.pdf
    • https://cdn-cms.f-static.net/uploads/4366375/normal_604b9d26f159b.pdf
    • https://static.s123-cdn-static-d.com/uploads/4417329/normal_60b1e1ac5b6b7.pdf
    • https://kevanosum.weebly.com/uploads/1/3/0/9/130968994/sigadezedanuziw_dogowag.pdf
    • https://cdn-cms.f-static.net/uploads/4422180/normal_6013798973e9e.pdf
    • https://cdn-cms.f-static.net/uploads/4450878/normal_6020c1202e6e1.pdf
    • https://static.s123-cdn-static-d.com/uploads/4496810/normal_60b1a887b442e.pdf
    • https://cdn-cms.f-static.net/uploads/4381988/normal_603bebbf4d119.pdf
    • https://cdn-cms.f-static.net/uploads/4366987/normal_604cee92ae07b.pdf
    • https://cdn-cms.f-static.net/uploads/4449616/normal_6052045bb760a.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/3c037cbc-5683-48af-b72c-64a78da86bc9/camping_merit_badge_worksheet_2020.pdf
    • https://uploads.strikinglycdn.com/files/2a4996d3-a33f-49ce-bb31-449b20e77194/70744623325.pdf
    • https://uploads.strikinglycdn.com/files/bbd1a4b2-84a1-4845-af63-e58427d3d2a6/pilobile.pdf
    • https://uploads.strikinglycdn.com/files/1521968f-b6e8-45de-902a-3c53ec3c48c0/78600869138.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_off0000ed32.bin
c49ff2ada9327441ac963fa024eee374659423519be934f83997688790218a0e
pdf-font-stream PDF embedded font (sfnt) at offset 0xED32 5292 bytes
font_01_sfnt_off0000ff3f.bin
8fe73d45aad4c7399de05155c592ef35326d1bb5a0ab452bfaa099bbf3df4980
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF3F 10920 bytes