Malicious PDF — malware analysis report

Static analysis result for SHA-256 a27b3b9d6c3578fe…

MALICIOUS

PDF

75.5 KB Created: 2021-09-05 01:25:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3018913accfe47bcc0661c9a8a904426 SHA-1: 90169220a1cbc9fa7fdab4a5118e20d2dd5666bf SHA-256: a27b3b9d6c3578fe1c9157cec8b76d5f11e0aa2f3a4bef4f48649bf93841f691
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://geoodwierty.pl/files/file/43255096583.pdf In PDF document text
    • http://skrn.cz/pic/file/60469272979.pdfIn PDF document text
    • http://agriturismofattorialucciano.it/ckfinder/userfiles/files/74803545723.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/691ed6248040489f85ceee67242d6a19/28167453967.pdfIn PDF document text
    • http://worldtile.net/jangheung/userfiles/file/579635217.pdfIn PDF document text
    • http://lagrupacio.cat/file/31807508022.pdfIn PDF document text
    • https://tekdalyapi.com/upload/ckfinder/files/7306100588.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/40368263216.pdfIn PDF document text
    • https://soyana.de/js/ckfinder/userfiles/files/ramozananekabasu.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/16790051294.pdfIn PDF document text
    • http://alrehabourhome.com/userfiles/files/18770098094.pdfIn PDF document text
    • http://www.ccengis.be/applications/ckeditor/addons/ckeditor/ckfinder/userfiles/files/jikijeradi.pdfIn PDF document text
    • http://zamel2.pl/userfiles/file/sujafobobavajapedojalib.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/84232381615.pdfIn PDF document text
    • https://www.utn.ac.cr//sites/default/files/files/22955836169.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bcef143c8aa---torakomuzikojujen.pdfIn PDF document text
    • http://muskogeeroughers1967.com/clients/9/98/9899c641331876fb313f08ec475a0443/File/vapozexanom.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/22f91940acebed2ce8d1546a38d5a5b2/tofapanuwawironuranilu.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160aa82d8e690e---86308247716.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=usul+fiqh+pdf+arabicPDF 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_off0000c2fb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2FB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB0D 17752 bytes
SHA-256: 342b586154dd3ae09b37bd436e6e26bb7ece51e0cb59f6bd8001d11b9e322b4d
font_02_sfnt_off000108b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B7 10656 bytes
SHA-256: c5f180b9bf9cba3de398c23fbc2b4095c3d2f6c5b6a8011412662991bdbbc8f1