Malicious PDF — malware analysis report

Static analysis result for SHA-256 3933bea95b4f84c8…

MALICIOUS

PDF

74.7 KB Created: 2021-01-07 20:53:47 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 433c45984dd8a24d25246a0bc445ab59 SHA-1: 71eed0ed3d50d0e8198a9cb8a9baac7114a16d1b SHA-256: 3933bea95b4f84c8068755a64ca4fad32250c6ee7423d1d5bd943889be47b1a8
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a link farm detection and a critical ClamAV signature. The document contains numerous embedded URLs, many pointing to external resources, suggesting an attempt to redirect the user to malicious sites. The presence of 'rundll32.exe' in a URL further indicates a potential attempt to execute commands or load malicious components.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://traffset.ru/aws?utm_term=alice+in+wonderland+soundtrack+2010
    • https://woxukobu.weebly.com/uploads/1/3/4/3/134392577/e371b8.pdf
    • https://jotinebemoti.weebly.com/uploads/1/3/4/6/134681432/5936874.pdf
    • https://cdn-cms.f-static.net/uploads/4464525/normal_5fb5a550700e1.pdf
    • https://cdn-cms.f-static.net/uploads/4489975/normal_5fbbb2dbae356.pdf
    • https://sovopubi.weebly.com/uploads/1/3/0/7/130775052/niroselubesibaw.pdf
    • https://cdn-cms.f-static.net/uploads/4452386/normal_5fb357c75ea1e.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/lowuwofuxali/6562015880.pdf
    • https://s3.amazonaws.com/vebogotexaf/11531282730.pdf
    • https://s3.amazonaws.com/dukexajuj/causes_of_depression.pdf
    • https://s3.amazonaws.com/wutezigojuxi/97649788697.pdf
    • https://s3.amazonaws.com/leributafa/rundll32.exe_keymgr.dll_krshowkeymgr_command_line.pdf
    • https://s3.amazonaws.com/zetare/neruwedafefaduxasubovori.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_off0000e68c.bin
3cabaded399c303495e2136b1f858dc3f414bb6ab7afcc8a7de4fbe1bd74c513
pdf-font-stream PDF embedded font (sfnt) at offset 0xE68C 5404 bytes
font_01_sfnt_off0000f911.bin
5bd083a475aca1412a6925c249b667021d8f9e3243b08c374626b7fc4b4a38ab
pdf-font-stream PDF embedded font (sfnt) at offset 0xF911 11052 bytes