Malicious PDF — malware analysis report

Static analysis result for SHA-256 651ac33f22bec6e9…

MALICIOUS

PDF

77.8 KB Created: 2021-06-20 17:16:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: d743f5b07ead1f75e316a2a02990fc37 SHA-1: a1519a32dbaa44664d0db61f86574d6f1ef1cab6 SHA-256: 651ac33f22bec6e9e77dccd14f2e5ca690468ea3654d7ce7f8a28d353695679f
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to compromised WordPress sites and potentially malicious URLs, likely as part of a phishing or malware distribution scheme. The embedded URLs and the document's structure suggest it is designed to trick users into downloading further malicious content.

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://medvor.ru/uplcv?utm_term=the+millionaire+next+door+free+pdf+download PDF link annotation
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/69htqscm37ihmnjqs1oivi7c9i/72219926832.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094de41a5459---foxusefoj.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607687bfeaed7---11651649407.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6b1321941---katonawewo.pdfIn PDF document text
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160815099d4e3d---2645885335.pdfIn PDF document text
    • http://laweasy.kr/userfiles/file/15974429692.pdfIn PDF document text
    • https://orldoc.ch/wp-content/plugins/super-forms/uploads/php/files/78ikfi21mjmmr7chbk8b5r2ir6/33371809456.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/200218401289.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608081e3823ca---zawamukasaniwudifowutu.pdfIn PDF document text
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607037a6a0d19---kepakinojorato.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/477f254fd5e547305c07f6a951482700/55015133723.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c325876465e---13976139799.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce89ee78f0---najane.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6f0b9ff11---lusemozipixarozan.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/e998ee32fee4ec505add44bfb9c1ac76/18271394602.pdfIn 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_off0000f110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF110 5212 bytes
SHA-256: b9accd91ba071500d9ba32cc5db0f01032e123648d75688e4ba63665bc5008d6
font_01_sfnt_off000102b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B4 11516 bytes
SHA-256: 2b407f5d1963dd641cc38abe6f6cc8b68e7eded3cbcffe468fad795be9bb8b6a