Malicious PDF — malware analysis report

Static analysis result for SHA-256 8eda61e3f7e56347…

MALICIOUS

PDF

82.9 KB Created: 2021-09-15 19:07:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3b322e5bc211e8431a8326886d430364 SHA-1: bc1711ca37ed582c4848df67b1822563a4a70706 SHA-256: 8eda61e3f7e563477d8dce4d608297be3ee063e2577c8e16ba054ba1933b3e9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains multiple heuristics indicating it is a link farm, with several URLs pointing to potentially compromised websites or disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The document body is heavily obfuscated and does not provide direct clues, but the overall structure and URL analysis point to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://stauarchitetti.eu/userfiles/files/99757155518.pdf In PDF document text
    • http://clingac.es/d/files/videbus.pdfIn PDF document text
    • https://estoniapools.com/contents/files/dipapejonilavurip.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/41149948492.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/30117826120.pdfIn PDF document text
    • https://dichvuhappyhouse.com/upload/files/35293316302.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/dekagavigezasosed.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613075534541a---kakosemejopanamugivezuj.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/mepejavube.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210901_150556.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/37063152444.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/baxoxajodixev.pdfIn PDF document text
    • https://alpinismbihor.ro/app/webroot/files/userfiles/files/98060197130.pdfIn PDF document text
    • https://cmflower-kkc.com/ckfinder/userfiles/files/1904272817.pdfIn PDF document text
    • http://pagyesa.org/userfiles/file/20210912204559.pdfIn PDF document text
    • https://asi-filter.pl/files/file/wakoreludadolideb.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/687517581.pdfIn PDF document text
    • http://15449010.com/FileData/ckfinder/files/20210914_050FAF4FBE7086D4.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/869785711315b95db33567af255233d3/movixegin.pdfIn PDF document text
    • http://peknanevesta.sk/media/file/727755042.pdfIn PDF document text
    • https://kottayammedicalcollege.org/CMS/ckfinder/userfiles/files/dowozagurov.pdfIn PDF document text
    • http://guchen.ru/d/files/pulevuzogox.pdfIn PDF document text
    • https://cristiandellavedova.com/wp-content/plugins/super-forms/uploads/php/files/3f776810c751e684686360eca5c3e21e/1445440730.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+win+friends+and+influence+people+latest+edition+pdfPDF 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_off0000d912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD912 19604 bytes
SHA-256: e8a72e0c7651f74c4eebef1d9914f5fc958a5eee4d643198b62776f39273ab3c
font_01_sfnt_off00010c6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12481 10792 bytes
SHA-256: b32dbd19fb2ce2e2272b21a7076f72c9a82fb7b497d7bda898ee4755a9acd37c