Malicious PDF — malware analysis report

Static analysis result for SHA-256 057536a1639b3783…

MALICIOUS

PDF

169.0 KB Created: 2021-06-13 11:22:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 5c9c825f4f38f194a6bc626b9e84ef5d SHA-1: 344622f9531faaf25f3fc830914847fb9c293c2d SHA-256: 057536a1639b3783748cf37f917143e24bec8579e68597900b657500d4fc4c1e
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-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://irlanc.ru/uplcv?utm_term=css+font+family+serif PDF link annotation
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072b0c9a8418---zugagafatunufoxesejifax.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/fce5eb38203be6ae4711f9b9a9a418cc/donibeketunom.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16086821792374---20048102911.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/2887607086.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1607c95bfd7c41---kisirojuvuxowes.pdfIn PDF document text
    • https://www.sudburyhighspeedinternet.ca/wp-content/plugins/super-forms/uploads/php/files/d4e48289635f3a50691440a6240bc77b/toxiwiselivawezuwe.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/rcqpkasrbq9unb9ce5uhhv9lks/4990888296.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/38116821225.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/93c4773fc58b7a8549a475aa4c255944/donisepikunabofod.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/662f993cf5f1556ce135f23aebf4d867/23002404768.pdfIn PDF document text
    • http://starlightcelebrates.ca/clients/4/43/43e9139217482d7666ce300faf566241/File/80023156460.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a2a42a33f5---tuvetalusu.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/mudj5mcrvb6ohfa3go1934kgqj/47965095572.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000e626.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xE626 127080 bytes
SHA-256: f62d745a3a0683e1d943ec8b0d1f5f7237019c24c2a5a71d855a68295770ac76
font_01_sfnt_off00025e83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25E83 4920 bytes
SHA-256: 8a4b63214e42b87202cf4427dc8380347e71ae7c1a2979f5a8feaad0542fc347
font_02_sfnt_off00026f30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x26F30 10912 bytes
SHA-256: c4e13a24da8e57a6406260507cf2693010be2b9c44ab1a2413126e20c88d8b30