Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c5bf75724618c2…

MALICIOUS

PDF

70.7 KB Created: 2021-09-24 15:50:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1d651232565a07fb543e09dbcc3e6335 SHA-1: 4a8510f9c9a55e957a219e66841b1efb6249fe92 SHA-256: 23c5bf75724618c29450345630e923953c67b45d4d5c38748131772b9a94d944
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm heuristics, indicating an attempt to redirect users to malicious websites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the document structure and URL patterns are indicative of a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://archism.ru/uplcv?utm_term=android+studio+dialogfragment+example
    • http://luxlustry.ru/img/upload/widawitipegajubavogi.pdf
    • http://ebbers-schilderwerken.nl/uploads/files/52895749895.pdf
    • https://kohphanganhotelandtour.com/userfiles/file/74100575785.pdf
    • http://adance0112.com/upfile/editor/file/lakaxor.pdf
    • http://hadt.vn/upload/files/jijej.pdf
    • http://tl-maskinfabrik.dk/userfiles/file/24491421051.pdf
    • http://hodinovysoused.cz/upload/file/mapiberosamejesekudufom.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613bc429e062c---58667714136.pdf
    • https://gdwtechnology.com/fckeditor/file/
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/99031658706.pdf
    • https://www.hmgfinance.com/ckfinder/userfiles/files/76554963974.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/4dfe5cdd77d1c53ea89969be7108d056/zazazamimobilumix.pdf
    • http://architettorobertafasola.eu/userfiles/files/29535614852.pdf
    • https://siltri.com/fck_upload/file/4658751840.pdf
    • http://itineraire-consulting.com/ckfinder/userfiles/files/pezigubexinejepu.pdf
    • http://lukoilmarine.com/ckfinder/userfiles/files/laguvewopot.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613659a3a026e---81691891147.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/16136754d8fccc---38024640057.pdf
    • http://nissanotogovap.vn/uploads/images/files/8888198489.pdf
    • https://masterjobintl.com/ckfinder/userfiles/files/bimakaviwidufodelitov.pdf
    • http://xn--z92bzy85x.com/userData/board/file/75885475574.pdf
    • http://thibidi.vinadesign.info/uploads/images/files/7471688404.pdf
    • http://maristaslardero.es/userfiles/file/budezazu.pdf
    • https://tssch.in/tssch/application/admin/uploads/file/61971192074.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/16138e4da2e141---vowamitovev.pdf
    • http://broadgatecapital.com/userfiles/file/xupetoron.pdf
    • http://neza.cz/UserFiles/File/16365625171.pdf
    • https://rugsdirect4u.com/uploadedfiles/file/jemomurupuzezubupi.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b38c.bin
5982cee79b3a5bfad87de2d2965955308adb622b417cfb4cb9d074567bdd8847
pdf-font-stream PDF embedded font (sfnt) at offset 0xB38C 15192 bytes
font_01_sfnt_off0000d9b4.bin
cdf4ec0682ae9db498dd6f73e0fc9eb6ba46e1d38b55e3e4b829c5eb8b41dc5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B4 11024 bytes
font_02_sfnt_off0000f32e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF32E 16792 bytes