Malicious PDF — malware analysis report

Static analysis result for SHA-256 10686633704a4603…

MALICIOUS

PDF

73.8 KB Created: 2021-10-01 11:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 06c1aae449c165530f70f4478947541f SHA-1: 24e633c38175a09111a9fe61ba4c0108610faa13 SHA-256: 10686633704a460321c9b5c475c976caf5f0617e4804815901562b22d9f68118
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16151db1d2faa7---63501050919.pdf In PDF document text
    • http://stellar-toys.com/ckfinder/userfiles/files/41354257592.pdfIn PDF document text
    • http://maschimaurizio.it/userfiles/files/63585066090.pdfIn PDF document text
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/5ff2a1d4f12e8b78343666d2a599eeac/27505241529.pdfIn PDF document text
    • http://claudiamelchior.it/images/file/govik.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/zisupakamosokolasul.pdfIn PDF document text
    • http://danieldesignpro.com/userfiles/ratitutazagufetetasu.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/xiroriw.pdfIn PDF document text
    • http://kerrya.com/ckfinder/userfiles/files/91148891863.pdfIn PDF document text
    • https://curtain.jinware.com/upload/files/kawoloziwozox.pdfIn PDF document text
    • http://kovacsoltvaskerites.hu/images/file/wojewepulekaweket.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/raroxisiwipofit.pdfIn PDF document text
    • http://linpus.com/app/webroot/userfiles/files/busadunusaxavalorubo.pdfIn PDF document text
    • https://insinkerator.us/images/uploaded/file/27965146051.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/nipizavejimum.pdfIn PDF document text
    • http://www.themixchange.com/userfiles/files/dofirelupikupaxorezanafod.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16149a3da24095---xafisuwosujabavukojam.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/oh3e85dc9kb1uioslsq42c7cj7/22011613051.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/biputixelivogijako.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/38685282817.pdfIn PDF document text
    • http://chinajessie.com/seadata/data/uploads/img/file/163139930264.pdfIn PDF document text
    • http://unicorn-furnitures.com/d/files/98354015448.pdfIn PDF document text
    • http://orosweb.hu/userfiles/file/5418106554.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/31113263215.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=world%27s+top+economies+2020PDF 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_off0000b790.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB790 10784 bytes
SHA-256: ad6489124eb2851935a525773c0935da1e92dc112fc9caa1d2390ddd8d3c1006
font_01_sfnt_off0000d06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD06D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87F 19212 bytes
SHA-256: 82ca512f3d022f87fd91d5e6109bab71bd07677b248e99f143ba7d382626aaf1