Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ecb3d8822ff0ed…

MALICIOUS

PDF

83.4 KB Created: 2021-08-26 13:55:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: 14edb74de1c78279d1c8c3a51f385a62 SHA-1: 11f12c6887228694b6369f23a1a6b057da5051cf SHA-256: 28ecb3d8822ff0edd1820f08455367fa425d5798f2c78cdfca7f210cda6774d5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO poisoning to redirect users to malicious sites. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://drafthe.ru/uplcv?utm_term=best+melting+cheese+for+burgers PDF link annotation
    • http://www.dereformasenalicante.com/archivos/files/temotivejiduzotukovonego.pdfIn PDF document text
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160880127a8f47---mawigubopowazusosebo.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/mukekujezigirozafesak.pdfIn PDF document text
    • https://berbagiangka.com/contents//files/54027121932.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/6927498727.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6946de38d7---36646050853.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/79187631163.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161053fdf760d0---10789788644.pdfIn PDF document text
    • https://ocbond.org/userfiles/files/91202912492.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/3i66c7tnff1ti0k568mmkuquis/xapapupusobune.pdfIn PDF document text
    • http://jodhpurheritagewalk.com/images/file/11988006510.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/43555916958.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210707_090448.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16079b41372090---82338623954.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/nagukinedib.pdfIn PDF document text
    • http://kientrucsangtrong.com/plus/files/70447676609.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/jigafununezifaxarijiximog.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/su2u6un8eifku6luq3lu980dp0/16891717723.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/161040b0c1db61---fowezutesikewenupuzo.pdfIn PDF document text
    • https://tripleccompanies.com/wp-content/plugins/super-forms/uploads/php/files/1d843bfba4362e9e605da9ccf3c0c352/85575293476.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae935a74cb7---dutevazewasaf.pdfIn PDF document text
    • http://anchor-m.com/js/upload/files/komidamujat.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/3d8a7ea2839e328ba1ff89006e990974/13837242985.pdfIn PDF document text
    • https://mariellatriolo.it/public/file/nemipuzifemineziga.pdfIn 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://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_off0000e28d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE28D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000faa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA4 10916 bytes
SHA-256: 54289afa6d94daff9074ebb92eb5da7003433348ae2fe198ca4c9791537d3c63
font_02_sfnt_off000113af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113AF 17028 bytes
SHA-256: 31f3354926ff7af566ca2d6b81d1afc50c27002858c6902723283e5647922b39