Malicious PDF — malware analysis report

Static analysis result for SHA-256 713915c5334c7b56…

MALICIOUS

PDF

78.7 KB Created: 2021-06-22 16:01:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: ca13860cf080fc81abad36b48df7e372 SHA-1: 6e60ef2c2deacc899efb6ec3c16d074390d534a0 SHA-256: 713915c5334c7b56ce18e12a731d9f6341c9c451bfb03a92837029cab01c49fa
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, embedding numerous URLs that point to compromised WordPress sites, likely to manipulate search engine results or redirect users to malicious content. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or SEO poisoning attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://queure.ru/uplcv?utm_term=basic+c+programming+interview+questions+and+answers PDF link annotation
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/3edcb75d0e233dc09771e4c972843043/jurokefujujegeseka.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/38af0f0776fb87a9383f4a35a184c931/napopit.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/432e5ff2cc5840a5388a68047aabde5d/logepefabe.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16094876eb0294---tivabufikazamebuvasirag.pdfIn PDF document text
    • http://www.bluewhaleline.com/image/upload/File/88365721918.pdfIn PDF document text
    • http://fouladsazanco.com/Upload/file/lawiwimebetikipo.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/fiwavebidel.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/stk5vp3cala2vd1sv4gdrnhr60/numop.pdfIn PDF document text
    • http://artospace.com/pics/file/31531632522.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7718a8e03d---20800502846.pdfIn PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/diwelimobusagurupibogil.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160897cb9e2ef0---zivexaz.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/74cd572370add0b14c1b2f0029b9d634/52572696974.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608706be3741b---lupuwesi.pdfIn PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/a87a61a0de7973f4f0cd722e16013323/64029060884.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e666.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE666 5572 bytes
SHA-256: c50bae10ca671ef45902a633d6f49d90771d80aacd21b37dd0842b3a69d2536d
font_01_sfnt_off0000f941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF941 11248 bytes
SHA-256: 61c635ff974699895cb5b0dbb8acc6913a09db374cd88b3ec89926a7f279f424
font_02_sfnt_off00011fa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA5 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3