Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f0bdcb5a33f5d33…

MALICIOUS

PDF

67.7 KB Created: 2021-05-10 15:10:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: e5283d816cd5a7508b467408d4ab613e SHA-1: 34519aed290c723d7ab1194c514a8bee005963d6 SHA-256: 4f0bdcb5a33f5d3360215fc9820eb18308555054313d64efb3a007588eb09591
156 Risk Score

Malware Insights

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

The PDF file contains numerous links pointing to compromised WordPress sites, suggesting it's part of a link farm designed for phishing or malware distribution. The ClamAV detection and ML classifier strongly indicate malicious intent, specifically identified as Pdf.Phishing.Trojan. The document body, though heavily obfuscated, contains keywords related to 'cheerleading uniform packages for youth' and 'wkhtmltopdf', likely serving as a lure to disguise the malicious links. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing campaigns.

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 https://wastran.ru/uplcv?utm_term=cheerleading+uniform+packages+for+youth PDF link annotation
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/a77e298e148a8c06b3befeab7c72ea5a/12659011386.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b76fc0dbc7---gozibozavumofojavozil.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160798f4dd8535---48418117790.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160710876840c7---77099273007.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1606f64010a1cc---fuvitetebokiworavi.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe6c3a7676---24236178701.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/a8mdmsrtm5kgn0opaknh0drr53/39950430046.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb4ae2611c---pizurezudaxofa.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6d3ca7b77---vanubojonogilewatumu.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075506592d44---rufaturixekisoseduj.pdfIn PDF document text
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/4lqh987s28gcija32e5285ck3i/jefosigapagekimoka.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/c05f51567dcc9408db8e9f365a5200ff/2832387035.pdfIn PDF document text
    • http://www.anieliasfx.com/uploads/textareas/file/zipufijamelukixosenoda.pdfIn PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/4aa5bacb9e2a691c60a244adbe347688/16125603858.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_off0000ca70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA70 5640 bytes
SHA-256: 19f30423435082c1840e3b2036a452f5d311c0772971d5cd9d51ffd099f64820
font_01_sfnt_off0000dd7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD7C 10688 bytes
SHA-256: d6a7b630f293b9a91be32f887c68176318656025092f7403efadda654d201dc8