Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb1e866974791bd5…

MALICIOUS

PDF

69.3 KB Created: 2021-06-24 17:17:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 87fced7ca2fc5e4af85c654f43fe5eb5 SHA-1: 38e3f9f38baed9e715a583d4a7409e5e8b8f7d70 SHA-256: cb1e866974791bd5995f9afaeb7c3a6fade9e4038c396f27894e52b68ce019fe
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites and disposable hosting, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. While no scripts were directly extracted, the structure and URL patterns are consistent with malicious PDF lures.

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://infrive.ru/uplcv?utm_term=research+journals+pdf PDF link annotation
    • http://castrolmintabolt.hu/images/upload/file/75515384740.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/1231705811e0f7647994b220cd15a3b2/34833205024.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210504072837.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/mbjb40t2vocupbg7qureaa4g19/monisuvogekitofaze.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085e9c300781---53880745734.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/6sl8qnrjjfnikf5om6bokj93eo/9394690143.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/lukuwi.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a5a7f41c82---nifepuradurifaz.pdfIn PDF document text
    • http://kapelski.pl/userfiles/file/74718121702.pdfIn PDF document text
    • https://chp-travel.ir/data/file/lozojemavafanukupegizuja.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160899803b62a0---22235321522.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/83361379497.pdfIn PDF document text
    • https://europartner2.pl/uploads/80898273595.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/laputaxaxugos.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5d7213bc8---dajutujopetolega.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086192f4c1ee---72375951648.pdfIn PDF document text
    • http://nesthomes.in/userfiles/file/51533280396.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/topojuwukuruxu.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_off0000cf2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2F 5328 bytes
SHA-256: a4b327bdb0b8f079f9cbec934a2b4314c66f671e9b04fc622bc28d2e4680f580
font_01_sfnt_off0000e14e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE14E 11528 bytes
SHA-256: bc117806f6e010f2e7b7f0c80cba5a06fe449179caf93690b1360bc12fc4171f