Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d657cebac9e0ff9…

MALICIOUS

PDF

83.9 KB Created: 2021-06-17 08:36:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: a20230ec52135f337539ce628bf2134a SHA-1: b8e0a9af3aa37b441b8fb3ca208ae75c132aac19 SHA-256: 8d657cebac9e0ff9ce7134e2d9884beac8e1bc033f490172907fa20f8adfba4c
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 0.9996

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://catamma.ru/uplcv?utm_term=free+uc+mod+apk PDF link annotation
    • http://guchenes.com/d/files/25448551624.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c913fcaf544---1706988270.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/60b15e0884acf7756325de3372a0e1d2/jazevuvapojipoxotifamimo.pdfIn PDF document text
    • https://fotoprint.lv/downloads/file/55370715502.pdfIn PDF document text
    • http://psychoterapia-przemysl.net/img/userfiles/file/sizefanebawudawepone.pdfIn PDF document text
    • http://greece-ex.com/images/blog//file/8420258792.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/6ea011b2bacab2371e141bc469173fbb/nalojorexugurewikanolas.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file/%5C/7979421480.pdfIn PDF document text
    • https://beaszemin.com/files/30865193076.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/16093485b8c5af---dibesalaregasomo.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe04ed40b1---45082631664.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/0lt70ho00p16bbpdaaipp6acsf/24151349328.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/44585234209.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e89d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE89D 5028 bytes
SHA-256: 7a3fcf76b334197ba80e796a6760dc091a19db8f6c5f11a00d2dd60411488332
font_01_sfnt_off0000f99b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF99B 1688 bytes
SHA-256: af3b288390c8e9d0f726e4a6788b3839931e9963a02079ff27995e2956f64111
font_02_sfnt_off000101f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101F8 11012 bytes
SHA-256: 6f3e679ef0c84a3cf5ffe60abc991cdea8e65b96844e56b0f6ad99b23a904cfa
font_03_sfnt_off000127cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127CB 17272 bytes
SHA-256: a4b3ce0bb012adf22ad1fce4758f2e0acc02b49fc0e97fd995ed71989e8510f0