Malicious PDF — malware analysis report

Static analysis result for SHA-256 9160479b88c232fa…

MALICIOUS

PDF

78.3 KB Created: 2021-05-02 07:48:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: f0eea7169100e1b35d0453cd933a3d89 SHA-1: 56c24f9197ffa0bacfbe1fdc652499c4e51f543d SHA-256: 9160479b88c232fa1688a4ebc3ae943f71e59f48ce3ac6d7b2b243c8916e5bc1
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content or phishing pages. The document body is heavily obfuscated and appears to be junk data, offering no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/1b26240c4d87f7b6674daa028aeae00d/34099910454.pdf In PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/0b709bd18ce8706d08ee714c2fd0834a/6339322744.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/f9854d81e094e9f5ab6a2a34eafcf060/83371675702.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb06b02caf---pebolunuzusimevotaxis.pdfIn PDF document text
    • https://refour.eu/wp-content/plugins/super-forms/uploads/php/files/3252036fb6db98d9bf31cb095e19d2c8/sadapelu.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608724382031c---wokenovinukopir.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/ejb1v4mik6t9eca3cf15imqvt0/kafefawitolu.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e2d81d002---xumotatajogibelomejor.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/jos05nhd8rcop7vqfs2sls9ss5/lunerigotasovev.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607a450593817---nibobadobekapobasazozofoz.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/2e9bf8e17285a585996f9fada452d497/kopenajex.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4d08db5d6---fafaxuvemexasoxe.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608ad791cd82c---kewopegez.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082812f97694---fopoti.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b114a82b55---pesula.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/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=aeolian+processes+and+associated+landformsPDF 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f72f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF72F 5288 bytes
SHA-256: 69957c1285f75974268cfd816b9a37e119e541de619b102a6f471f81ac7968b5
font_01_sfnt_off0001091a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1091A 10412 bytes
SHA-256: 2a972a947953bbc8af80f64cf2f8eb1a29f21c978846dc6686d8738562155507