Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa311541494c980c…

MALICIOUS

PDF

71.9 KB Created: 2021-09-25 06:32:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4941a848ff79aaf475d298874593519c SHA-1: af8d91e030d8f8fa1525e0f7f14f83b59f9c48ea SHA-256: fa311541494c980c6b5af086d1581384c69b172b9db0015694c0a3660e39cdd2
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or are hosted on disposable domains, suggesting a phishing or malicious redirection scheme. The presence of a link farm indicates an attempt to direct users to external, potentially harmful, content.

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 http://rkenterprisesonline.com/FCKeditor/file/18331243774.pdf In PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/mofixuzeg.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f671a3595---34176534057.pdfIn PDF document text
    • http://studiotecnicofrisoli.com/userfiles/files/53927612231.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/pazuramasumamevufewipod.pdfIn PDF document text
    • http://wang023spa.com/userfiles/202109file/2021090701595370554.pdfIn PDF document text
    • https://2-view.org/home/view/public_html/ckfinder/userfiles/files/67655882240.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/94161777178.pdfIn PDF document text
    • http://farmina.ru/uploads/files/39299782711.pdfIn PDF document text
    • https://kopari.hu/files/file/15022376513.pdfIn PDF document text
    • https://samajsutra.com/userfiles/files/80203869995.pdfIn PDF document text
    • http://xzass.org/ckfinder/userfiles/files/gogum.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/37863351182.pdfIn PDF document text
    • https://hetodon.com/fckeditorfiles/file/29021366943.pdfIn PDF document text
    • http://twapp.freshkon.com/upload/files/zomasizupu.pdfIn PDF document text
    • http://architettoannalisatinelli.it/userfiles/files/mukezolizukilu.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/5a6a9c5b5df29aeb706a6f816b03880c/90653498746.pdfIn PDF document text
    • http://herium.net/FileData/ckfinder/files/20210912_5B03955B54204755.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109081734493265.pdfIn PDF document text
    • http://bjqyms.com/filespath/files/20210923183220.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/f90f19fe48950fe7cf6592db69ec2406/53101491136.pdfIn PDF document text
    • http://webbuilders.com/files/file/xebaz.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/92167921552.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613f86391a570---99499420894.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=change+lockscreen+androidPDF 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_off0000b443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB443 10676 bytes
SHA-256: df974036e13a862eeec815699da338d8473357036189123a5583c9cb8aa9444c
font_01_sfnt_off0000cc70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC70 17844 bytes
SHA-256: 22efe31bf15a0d220299437ad99cbf4e4894afed58b6d1b3cef2b0d1e8a73553
font_02_sfnt_off0000f9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1