Malicious PDF — malware analysis report

Static analysis result for SHA-256 efa4842cefd04b8f…

MALICIOUS

PDF

76.5 KB Created: 2021-06-10 05:50:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 3eed67aa9a2cb15acf7f1cd1af018c08 SHA-1: d5fadf9b9dc4c87ff0c3b07b23598ca6497c46b4 SHA-256: efa4842cefd04b8f2b7eff062585725e730ec9567d46988aeb6952d7220cc8f1
164 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous URLs pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious destinations. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or a scam.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=problem+involving+fractions PDF link annotation
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9a538df9c0---68922890621.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607689d61bc2b---49037616410.pdfIn PDF document text
    • http://brilspa.ro/userfiles/file/%5C/85131196052.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3db2005df---movatozisenibuvoda.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/ded72772b135bac7bd4e6affdd5ede93/65258606715.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b6840710f---definip.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d00980b763---tobumirasi.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607beebd2f8a4---waremezunuruxa.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/1915spdlst0k7fnmca3i97tg4s/rufulatupitu.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/vgsrum72e9cffhhn0eju2okkka/50576606336.pdfIn PDF document text
    • http://kaizousha.com/js/upload/files/sejoni.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/v7o3llfrmfi8326dtvmstvk082/68400256050.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/160934cd12f6a3---87250366928.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/91155250753.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/gihlrkr11s6mp9qpspntatjfp7/73529501302.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/95889aa2aa064b90f49635d0fe95ed02/bodiviwi.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e988.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE988 5404 bytes
SHA-256: 2fe2933279f998bc64e795c65d262af05578a6156f5608d683a81d6aef9103a5
font_01_sfnt_off0000fbe1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE1 11916 bytes
SHA-256: 4a20589243bff0c6911694ade6ab0fd27fa78990e27131a4045155a51a432f7a