Malicious PDF — malware analysis report

Static analysis result for SHA-256 841373207d6b0028…

MALICIOUS

PDF

75.9 KB Created: 2021-04-29 19:11:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 8544d5d4ae46d45dc7d21c4a7d69bc82 SHA-1: df2acf8f5143e996b62648d53f2779e6ebe32027 SHA-256: 841373207d6b00281098fc9324511b8c68361aa1d7d5f78b760210b6dd261eff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The document body is heavily obfuscated and appears to be junk data, suggesting the primary purpose is to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/0f45095baf0cfa63a12519f1c39c140d/45042098968.pdf In PDF document text
    • https://www.certificagreen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160768637859ff---sowuvoriribonasomavi.pdfIn PDF document text
    • https://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c2c3f5d90217aa4ebc16dfe0bda82add/woralamu.pdfIn PDF document text
    • https://dmvassociates.com/wp-content/plugins/super-forms/uploads/php/files/7ef6c73e0099b2b53fda95d17b203afc/vedizivapiranuwuwi.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/23907792137.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4ed8a6814---53832100685.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608485411a5dc---53560848496.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607c72a6d289a---rugixaguremujoxuvebop.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072f2b14724a---tarefaropiti.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/2f1ba741d710c5a209cfd33c38b9c272/jilatazedexewajoj.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/160808023934ae---jamon.pdfIn PDF document text
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/3a04daa4d108cf6b63cd6a5679d053bf/xasuvaligarawepugufikibe.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/uoictfcmnp35n2a363oo57uegu/faxeje.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/93781666261.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/FevRqgeaUVY/uplcv?utm_term=nagpuri+dance+dj+videoPDF 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c92e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC92E 5136 bytes
SHA-256: 2abecbd13059fe19c9f2de9454d4b493d94cdd9f8b52b95fe1bcece6579cfb07
font_01_sfnt_off0000dacd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACD 12112 bytes
SHA-256: 27d8bc3343e0d60c0fb76b394fa7646c680624cfe4c8ace6826005543be9a9c0
font_02_sfnt_off0001037b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1037B 18624 bytes
SHA-256: e7bf75170afe13b3e63ad7f3c0cf0d945cf07321de139f9a1070e265d25140c6