Malicious PDF — malware analysis report

Static analysis result for SHA-256 97ef5af5d135e5a0…

MALICIOUS

PDF

85.9 KB Created: 2021-05-27 16:12:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: f69f3e59258a7dab77a18fd4877434b4 SHA-1: 0c07d3d224afa5282d7ca006a203bb92668d01e3 SHA-256: 97ef5af5d135e5a08acfe9b690cf5f5323a2634387a6938d331aa84b236c969f
156 Risk Score

Malware Insights

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

The sample is a PDF file that contains numerous links to external websites, many of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest a link farm strategy to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://crysiq.ru/uplcv?utm_term=internal+combustion+engine+fundamentals+by+john+b.+heywood+pdf PDF link annotation
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/c7j0r27d4ric5042hol9b2l267/83827748893.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16075f32eb3815---45015388359.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076e8da19a7a---rixobodojor.pdfIn PDF document text
    • http://animalscipublisher.com/files/upfiles/file/30273693281.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5dac66984---dadifuxanom.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083873962a83---mekifikup.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/f1070824ecd7b45c1e673793801d5fd8/dinidufoxowito.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a888252f17d---38166203867.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160818e064a934---3156406995.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b91fbc65dc---kivisiboso.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c49b20c2c---vuwibi.pdfIn PDF document text
    • http://mazdooradda.com/userfiles/file/depizedoburanonukezegopi.pdfIn PDF document text
    • http://nordicaluminium.ru/userfiles/file/18728370171.pdfIn PDF document text
    • http://mvclassof1990.com/clients/8/8c/8ca0ba2c7a07c5cd1f21f9fc323c16c5/File/xeluvapuragoxajumu.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
    • 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_off0000f501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF501 5948 bytes
SHA-256: 24ff7a2d40858b5ee5862054f0b320453512d71b2a899d7b79fe4dc0f8cacf4d
font_01_sfnt_off0001092f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1092F 12488 bytes
SHA-256: e6fbb652f42cb885127d0dc53e86fa8e6123437659ea9086f0610dfdf8dd8f27
font_02_sfnt_off0001338d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1338D 16456 bytes
SHA-256: 5433a1b741babf8828a6edeb8df7e162bba263b89b5bd149edeeb58ed7d6fe2d