Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9bc77a17136de8…

MALICIOUS

PDF

86.7 KB Created: 2021-09-10 13:02:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 237bc185917d96dc17b65df492a64333 SHA-1: 22f19685b7b5a76073bfadb4ce1e5d61075a95bd SHA-256: ac9bc77a17136de8f7a6a7b84129629927473130f1e74636072cf1e69bbef2ea
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised websites or disposable hosting, indicating a link farm designed to direct users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://vedepcuaem.com/luutru/files/26779405886.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/4369692c6708c7b491f1afc84ddc22ce/52456570720.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/444eb9bd71df442ac3d167fb1d689199/78750808481.pdf
    • http://cancunday.com/travela/img/files/58464660897.pdf
    • http://plan.msu.ac.th/ckfinder/userfiles/files/28358695626.pdf
    • http://alianzablue.com/aym_image/files/43747610546.pdf
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/ci097dit44f681lgdjtf3lqupr/wenipetipawela.pdf
    • http://gro-felix.si/uploads/54537508232.pdf
    • https://palcev.ru/userfiles/file/87837380003.pdf
    • https://csp-pub.com/stockages/files/vexotegaxetawojijugexojex.pdf
    • https://rieker-consulting.eu/files/file/43116866733.pdf
    • http://phuketdriveschool.com/userfiles/file/8706525909.pdf
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131b04465e59---16411664245.pdf
    • http://spc1991.com/ckfinder/userfiles/files/94481712902.pdf
    • http://esrafisek.com/images_upload/files/miwavalego.pdf
    • https://ibshospitals.com/userfiles/file/83271020789.pdf
    • http://www.hkimm.hk/_bin/ckfinder/userfiles/files/50819168054.pdf
    • http://www.highlandmetals.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16132a5b1af9bb---84292030031.pdf
    • http://soft-pro.hr/upload/datoteke/nalatobasasudi.pdf
    • http://hotel-ambassador-nice.com/upload/files/watig.pdf
    • http://essiac.cz/UserFiles/file/27385940497.pdf
    • http://tv-sat.cz/userfiles/file/kijewogulum.pdf
    • http://geologicatoscana.eu/userfiles/files/gafovegenirizokimidonorul.pdf
    • http://kaies.net/upfiles/file/fuxexototomi.pdf
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16131d47dea8a7---kimitor.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=app+to+make+font+bigger+on+android
    • 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_off0000ef0c.bin
a1e5534802812ec330249b99d2781e4c4f958fff791009cc78843f0ed230fd50
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0C 17584 bytes
font_01_sfnt_off00011cac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAC 16792 bytes
font_02_sfnt_off000134c3.bin
4131c02442b0d53e6d103cc7c2872f3f3e66d2cb8ee744467dce28db9e06b076
pdf-font-stream PDF embedded font (sfnt) at offset 0x134C3 10840 bytes