Malicious PDF — malware analysis report

Static analysis result for SHA-256 021b1fea6d9ff1d2…

MALICIOUS

PDF

71.8 KB Created: 2021-09-26 06:32:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3e1f42e9a1b13d5190a286a60ed625b9 SHA-1: 6f0bdc8e28e06d1cfeb349410cad5a01459b06d4 SHA-256: 021b1fea6d9ff1d2707e6e09fe863772d0a4584715aa477744cef6f28c07eccc
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs, many hosted on compromised websites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple links to potentially compromised CMS uploads suggests an attempt to leverage existing infrastructure for malicious hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://rabotatver.ru/userfiles/admin/27944112108.pdf In PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/ob5ug26lcep8gsnphrkp2uain0/48665696213.pdfIn PDF document text
    • http://thienlongadv.com/upload/files/86150402650.pdfIn PDF document text
    • http://hk-keber.de/images/file/4034261461.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130693c6bd77---30043986060.pdfIn PDF document text
    • https://ww150005.linebot.net/upfile/files/20210914041851.pdfIn PDF document text
    • http://nowyhotelik.pl/userfiles/file/69968416713.pdfIn PDF document text
    • http://www.guus.edu.mn/ckfinder/userfiles/files/kemuxosogerimunifemotuk.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/62805386559.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/7387172324.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/ridifanofarafituvigobadu.pdfIn PDF document text
    • https://zzhqhi.com/d/files/23629733543.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/zilavogojobubixixizi.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/ludajuwomi.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16145f2a9dd7f8---vilebigevibixasar.pdfIn PDF document text
    • http://pomelieagency.com/userfiles/files/kudodisozexur.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161336cc91f2f4---86527941863.pdfIn PDF document text
    • https://peusch.lu/userfiles/files/duvojajobojizos.pdfIn PDF document text
    • https://rugerwafers.com/demo/ruger/beta/userfiles/files/43089225258.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/90629589277.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161383c9bed7d4---kuxemulumadulilasuwijoseb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=sms+bypass+appPDF 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_off0000b326.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB326 10048 bytes
SHA-256: baacfb92d85f29ae24109ad155a9fb5c5a4c35e007e7668aed14d117a0e6b53c
font_01_sfnt_off0000c944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC944 18500 bytes
SHA-256: 624e54850c9d8c858481214193443c75e07905e27db9a967ae9d35564119e03f
font_02_sfnt_off0000f96c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF96C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1