Malicious PDF — malware analysis report

Static analysis result for SHA-256 57b53b200b455397…

MALICIOUS

PDF

77.5 KB Created: 2021-05-27 20:58:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: f59db6c184dda490e19733d6df6b1c35 SHA-1: 7744763b48d1947b78d894946bea1b24c45ea01e SHA-256: 57b53b200b455397c95015b6f047870cb17dee262c2355de154833da239f0c97
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://philabc.ru/uplcv?utm_term=what%2527s+app+gb+plus PDF link annotation
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/de2ecf91050269956936347da0d5936c/xajetiwufivigokikuxe.pdfIn PDF document text
    • http://saamfactory.com/wp-content/plugins/super-forms/uploads/php/files/de53ea258a4f2b1fe85760e59a7e067a/8226121494.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/b0kef2f62m99ac24d3cpnn3v2i/33259849796.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a2cf64114f5---70401382002.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/40bfb356345c634cfaf2e886c8cdf777/25455935788.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/584ce6360c47adde409727e3dff21ef7/nefamofidawozo.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cb9fa0e902---gunanemikekamewe.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160924ea035ef2---fejomupevisesenasawoxol.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a79544bf712---55046383547.pdfIn PDF document text
    • https://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/da9c1d2592bb073767ff43a71c418faf/76442785697.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607cdda2dee97---retarurozozubezurujamabat.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d236e8c2d4---40729132160.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/5lkog3etqv0nl67cj9oavhp6b1/venudetevutorobok.pdfIn PDF document text
    • http://canvangdientu.com/images/file/mezaxomilufiwet.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_off0000e3ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3AB 4672 bytes
SHA-256: 9db5a13d5657419af2a214ef38d91ec330179d7e81f79976f5bf1983fa3e27c3
font_01_sfnt_off0000f3a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A8 11712 bytes
SHA-256: 6f7d9dd57dcf83c8813953d743cc1dd33e4b0d06b086afdb7280f4bf00f341f6
font_02_sfnt_off000119df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119DF 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176