Malicious PDF — malware analysis report

Static analysis result for SHA-256 551b16d0dea044d6…

MALICIOUS

PDF

79.0 KB Created: 2021-06-21 20:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 62c83c4b9af7cb2f986ead4bf1e0468b SHA-1: 23141b4a46872775d2cf4fa6be600726c119b5ef SHA-256: 551b16d0dea044d60c7bcc7c493f32efc19812c8ed662d107ae097049fd9eb5c
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-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 http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160803d26874d6---xekuzuxegodi.pdf In PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b180d1c62---xalufa.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0fe785c73---lukisinopinadowo.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/mopoveza.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-4-29/20210429171731935986.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/i1802cd6ie6vql821s7l1aot7k/domar.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/kozagibexelofogifizoja.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8b029a0d8d---34039755013.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/5e434d3f7ef44b45d510893860a699fc/zunifabebinobixemarepemip.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/11561453830.pdfIn PDF document text
    • http://cortabellanews.com/userimages/jutadijepujeluzofoveg.pdfIn PDF document text
    • http://axwelindia.com/uploads/7062422441.pdfIn PDF document text
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/b278cb96a36a17d82cd9d229c393dc7c/vofunet.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/61386855135.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/355fqoqi5fa5u3tu7jvtplansm/zumenugikedisolaxivariges.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/8c9e04913fd16fd015a090b1f9fc8885/weneg.pdfIn PDF document text
    • http://www.toptehnik.si/images/soreworizifug.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+combine+multiple+scans+into+one+pdfPDF link annotation
    • 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16C 5400 bytes
SHA-256: 8a1f2572431fd0a9094c47b52152dea85ebb5f1d80da87b4b06ff28a8dd6d1fe
font_01_sfnt_off0000f3c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C2 10624 bytes
SHA-256: 9cb7ab368f2d71233f37867dd04c50ee22760473099656aeac7307d8c5084d3e
font_02_sfnt_off0001184a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1184A 16388 bytes
SHA-256: 792d94d721ed0b6f37dc0a2c63227a1e02ba985f3311c734d905b891e1ee35e8