Malicious PDF — malware analysis report

Static analysis result for SHA-256 c90a6db4a1b245ee…

MALICIOUS

PDF

82.1 KB Created: 2021-09-19 07:27:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2b209afca33016ceb041f70478d862ca SHA-1: 92ce1405c11bac5f899fd4eb1cb95dfbe51bef5b SHA-256: c90a6db4a1b245ee89a376038e09d721cdc556ebac337a3b031d8bdc0b760f6a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains a link farm pointing to multiple external URLs, many hosted on compromised CMS uploads, suggesting an attempt to distribute malicious content or phish users. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, likely delivered via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 http://sartor.ru/upload/files/69524505951.pdf In PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/vku51dc3o320fmdg7qs0hhhclc/woganitekajasizojabipop.pdfIn PDF document text
    • https://limadelimon.com/images/file/52168305065.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139918b11564---dibed.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16140cde869fc7---38627558782.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/39217011265.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/97543992159.pdfIn PDF document text
    • http://standartbio.com/fckfiles/file/45487707180.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc4216bb72---84129051928.pdfIn PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/99245964834.pdfIn PDF document text
    • https://priscar.com/documents/files/67500625022.pdfIn PDF document text
    • http://bentleyplemtech.ru/userfiles/file/41555707492.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/kudixajot.pdfIn PDF document text
    • https://www.sesc-am.com.br/Selecao/ckfinder/files/xetizudokewezemezoluz.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd46dd9b6c---14144166264.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/fimiwebava.pdfIn PDF document text
    • http://www.cemeba.com/uploads/ckfinder/files/17501321148.pdfIn PDF document text
    • https://avukatwebsitesi.trakyasoft.com/upload/files/62556482217.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/86952526628.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=jackie+chan+action+kung+fuPDF 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://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_off0000d6a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eebb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBB 19984 bytes
SHA-256: 228755874bf2556bc2c502d9a65f7f2352dd7cf19064fc68be22879266ad4ab6
font_02_sfnt_off000123d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123D5 10484 bytes
SHA-256: 6b36b970bbe025e471f0e7100159e943632605f6be228a0c45adc00eb380df89