Malicious PDF — malware analysis report

Static analysis result for SHA-256 77788b830a25eb03…

MALICIOUS

PDF

84.0 KB Created: 2021-09-18 08:59:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b015f97597993b450af8bb07e02a33a6 SHA-1: b2c07323aeae936c1bd5fa4fdcedf4da8204b2bc SHA-256: 77788b830a25eb031c740ce13d7b3454aff6b75800d50027a3498809e0bfda6e
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a link farm. Multiple heuristics indicate the presence of numerous external links, many pointing to compromised CMS uploads or disposable hosting domains. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and URL analysis strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 http://fijiembajak.com/uploads/ck_uploads/files/maburatejetutejamatad.pdf In PDF document text
    • http://antichigelsi.it/userfiles/files/bijozosuxa.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/13851258030.pdfIn PDF document text
    • http://modamoda.nl/uploads/pic_lib/file/43574991973.pdfIn PDF document text
    • http://warwick-ems.org/userfiles/file/41838270324.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16132c589bf4f5---depozeriwubumade.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/94678175517.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/kagisa.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/oe0hgfuf97jav115mmau0ellfk/wukuvukekibumas.pdfIn PDF document text
    • https://www.southdownscellars.co.uk/ckfinder/userfiles/files/28196569372.pdfIn PDF document text
    • http://machulski.com/public/file/lixatufal.pdfIn PDF document text
    • http://pietroquatriniarchitetto.eu/userfiles/files/69323118100.pdfIn PDF document text
    • http://eko-baby.ru/userfiles/file/21356108717.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/kapopunulodagokuna.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613e31bd17e86---zawafefogawewamaka.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141128c24a5a---1534844031.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/miziwujigezuwozota.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/43310663137.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/jetegixusurisuvuf.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132cfc15fc13---nezuviloxexolemiburigolu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=download+ppsspp+games+under+200mbPDF 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_off0000dbe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F7 20064 bytes
SHA-256: 5c1926f9985ca33b92316ba9b5e17ab6cfdb4edfbac9580f4fc7ee8b92571228
font_02_sfnt_off0001291d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1291D 11112 bytes
SHA-256: f615447224a42e9c15bb18ef69308240be822ef853553299db4046f562dda333