Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4dea8ddf3be59b5…

MALICIOUS

PDF

78.6 KB Created: 2021-09-22 14:14:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6678c331757cec23c755d226542f2143 SHA-1: 565bfba8894b26a8a476914669a643b5e6f1e7f6 SHA-256: a4dea8ddf3be59b55a2cdeba050f6cd699ec9d9dba43e11db9e9f72a7b6a17d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains numerous external URLs, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://archism.ru/uplcv?utm_term=%D0%B8%D0%B3%D1%80%D0%B0+%D0%B2%D0%B0%D1%80%D0%BA%D1%80%D0%B0%D1%84%D1%82+%D0%BD%D0%B0+%D0%B0%D0%BD%D0%B4%D1%80%D0%BE%D0%B8%D0%B4 PDF link annotation
    • http://nexxstep.nl/userfiles/file/78468544917.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/fijonozikebadori.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/files/18966799180.pdfIn PDF document text
    • http://geojeoceanhotel.com/userfiles/file/20210912063421.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614018d6d86bb---kivukokiwozulevodebewif.pdfIn PDF document text
    • http://www.texaco.bargiel.com.pl/ckfinder/userfiles/files/46816790913.pdfIn PDF document text
    • http://safarang.com/basefile/files/sibelikumavabib.pdfIn PDF document text
    • http://bagodilovaspark.hu/userfiles/file/12583520507.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210918_D408699B7E0829B8.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/25390667017.pdfIn PDF document text
    • https://fertilizergranulatorprice.com/d/files/paleweruwisizutigukabufis.pdfIn PDF document text
    • http://indcms.testingmachines.com/images/file/ledun.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/bugizabekomojazub.pdfIn PDF document text
    • http://jiehuist.com/userfiles/files/85420207039.pdfIn PDF document text
    • https://lapalettedesarts.fr/gestion/file/30768043470.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/tukoke.pdfIn PDF document text
    • https://anitt.in/ckfinder/userfiles/files/24263717562.pdfIn PDF document text
    • https://eagle-aviation.com/userfiles/files/23013557114.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/4555111840.pdfIn PDF document text
    • http://upsshop.ru/ckfinder/userfiles/files/50728658881.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/12566584190.pdfIn PDF document text
    • https://mediaget.ru/userfiles/files/tosunogepaz.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161475f16e1945---xemisaxu.pdfIn PDF document text
    • http://traditionsradio.com/wp-content/plugins/super-forms/uploads/php/files/e5367b049a1539d814c0c04bf0bf0f71/riteroxijus.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_off0000c086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC086 23796 bytes
SHA-256: 769c97945c0102b58fd91fec180eb4b715673ab9e9d800f92610eba048a09613
font_01_sfnt_off0000fa91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA91 10372 bytes
SHA-256: a1567488906de131b3cfd79ca0804107cd54913debfb271d06bc57ff7f1e017b
font_02_sfnt_off000111ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1