Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a7358e4313251a4…

MALICIOUS

PDF

83.0 KB Created: 2021-09-11 18:56:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8155bea9d5997a67da396e42780abc03 SHA-1: 35b7cdb55fd7e112ee1ce3d44136ad8d0ceb7325 SHA-256: 5a7358e4313251a471071c4709333580354060b648a33a45b3a9da55441840d9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a link farm designed to redirect users to malicious content, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with known phishing and malware delivery techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://archism.ru/uplcv?utm_term=how+to+put+live+wallpaper+on+iphone+12 PDF link annotation
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/89515371919.pdfIn PDF document text
    • http://swhos.com/upload/files/72996020473.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/4425848358.pdfIn PDF document text
    • https://greenfins-thailand.org/uploads/file/38842518281.pdfIn PDF document text
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/7316532540.pdfIn PDF document text
    • https://pellevah.com/upload/files/dosadojaz.pdfIn PDF document text
    • https://vilnius.cvzona.lt/resources/img/files/zabomerijiseme.pdfIn PDF document text
    • http://elsped.hu/files/file/mefubo.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1f50f24f6---98099158191.pdfIn PDF document text
    • http://lagerunda.it/public/upload/file/lateretawuserasurosu.pdfIn PDF document text
    • http://brkvinc.com/userfiles/file/lovusafakirowakov.pdfIn PDF document text
    • http://teresachild.com/upload/files/15809066083.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///labazarewi.pdfIn PDF document text
    • https://metricgroup.it/uploads/file/6623533199.pdfIn PDF document text
    • http://tovicetour.com/FileData/ckfinder/files/20210911_422288D42DAF3C4A.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/zelitabipasapemiwum.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/demugugirizikupakebib.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16131c76e1bcb4---nitilotozufaxepiveripanu.pdfIn PDF document text
    • http://cokhihoaiduc.com/uploads/files/4083567536.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/nuxevofipusum.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/jiwakejaf.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/sexoretasoje.pdfIn PDF document text
    • https://skvacations.com/userfiles/file/pijunugulakow.pdfIn PDF document text
    • http://pizzeriadevita.it/userfiles/files/labisovopan.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_off0000de6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f67f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF67F 18240 bytes
SHA-256: a1b61283f95a09da456dc40f070abb774f66bc7d19e773fdb34630bd18e217ad
font_02_sfnt_off000125d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125D2 10596 bytes
SHA-256: 363979c714633837857af59ef9decda837a8175062780d7996f3fd4f65d5a5db