Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b81919a227fb463…

MALICIOUS

PDF

90.1 KB Created: 2021-06-25 14:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 98006654f13e7739c8edc3a48711761e SHA-1: c4daa3d5a1f4a8f52efbd4933035086911d02edb SHA-256: 1b81919a227fb463b91417e5d04bd5b3980a0057bc94a7c8df38d6b1b5ece1ff
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. These URLs are structured to appear as downloadable PDF files, suggesting a tactic to lure users into clicking malicious links. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or redirecting users to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://jjmassociates.com/wp-content/plugins/super-forms/uploads/php/files/aba5254a82e777d566ff0c4ece10184d/72476994888.pdf In PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/5c725398a838d2ee9f99b53e7e53f041/xedolibogotevusixodaz.pdfIn PDF document text
    • https://triosms.com/userfiles/file/vamunu.pdfIn PDF document text
    • http://www.wiz-fac.com/uploadImg/file/zikisu.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/95ac5f8d6fdce39cf486e02b43c5ce91/silawikijizolojesobajos.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea4961080f---vazokose.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c756cc51a3---75484588577.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/1cd7898e69080466d4b81ffbcdc37ec1/63707225249.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/qrcdq22k0jmuf9ab9vq2qlcaf7/basunugazubekena.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/dfe5614b4c025527af85edbbcfddf8d8/nofuwovabujemi.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609630c5611e7---48393653181.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/fajas.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/65840392445.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b316ce9eb28---52176752332.pdfIn PDF document text
    • http://energo-market.ru/sadm_files/reduboni.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/h00568c7jonv79ir73bdd06n75/46650777026.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=the+most+beautiful+girl+poemPDF 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_off0000fd5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5F 10904 bytes
SHA-256: ebc29e4833e1d132a15697c0bb144122d96060026e955e5f9876d9b53b11f612
font_01_sfnt_off00011667.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11667 17456 bytes
SHA-256: b7eabfd56393c55dffee98461887a1b10f620249710b9ee8f98e44a93b223130
font_02_sfnt_off000143c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1