Malicious PDF — malware analysis report

Static analysis result for SHA-256 c37e3c4bb436b514…

MALICIOUS

PDF

78.3 KB Created: 2021-09-20 18:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a93797d29828c69ca845ca78946e3247 SHA-1: 1218cc99707bdaefd478e08fa621031dc8f7b245 SHA-256: c37e3c4bb436b51448e0ae9eff26c3e627b4f2c2bffcaf6c2831eeaab3cb7076
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading malware by presenting a deceptive link farm. The embedded JavaScript is likely responsible for initiating the download or redirect process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://synerhu.ru/uplcv?utm_term=street+fighter+1992+game+download+apk PDF link annotation
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/49525658c5149e1a9518e251e8082766/33522580968.pdfIn PDF document text
    • http://imbirimbir.ru/files/banofevojosenivebopenun.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/395e3bcc8c293083bb892265981a118b/xumusigoxalidusunujuzux.pdfIn PDF document text
    • http://jerseybankruptcylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/13304519410.pdfIn PDF document text
    • http://qazaqbanki.kz/data/content/files/30578122235.pdfIn PDF document text
    • https://samsungklima.net/upload/ckfinder/files/93862390475.pdfIn PDF document text
    • http://recko.ru/ckfinder/userfiles/files/netefisagasa.pdfIn PDF document text
    • http://xn----9sbbnbtte4cyg.xn--p1ai/ckfinder/userfiles/files/lefomaku.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161414dd950175---nuwejajifatax.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/32152057154.pdfIn PDF document text
    • http://awarelaxcentrum.cz/user_files/file/lexof.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/pipumalixuzorude.pdfIn PDF document text
    • http://sichera.eu/userfiles/files/87635175758.pdfIn PDF document text
    • https://bhopalliteraturefestival.com/mpsdp/uploads/files/77698945482.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/mujowewajudojafezuj.pdfIn PDF document text
    • https://nusamulticentralestari.com/Uploads/userfiles/files/janopovenafizimavoz.pdfIn PDF document text
    • https://all-stage-meditation.tw/uploads/files/6131f8496be94.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/16501611167.pdfIn PDF document text
    • http://www.w.radeton.cz/ckfinder/userfiles/files/zelopivudelafibevuzirari.pdfIn PDF document text
    • https://cpsguffanti.com/uploads/file/76274522923.pdfIn PDF document text
    • http://pscemetery.com/userfiles/file/zirugim.pdfIn PDF document text
    • https://redengewinnt.com/userfiles/file/89157484248.pdfIn PDF document text
    • http://finalstage.biz/js/upload/files/22880960072.pdfIn PDF document text
    • https://bunyaminerdemir.com/resimler/files/3091569182.pdfIn PDF document text
    • 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_off0000c977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC977 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e18e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE18E 11372 bytes
SHA-256: 35712f42cc3625a0c5f89281d6fe6406e3350d50d8fbf6d8708aa98942800e60
font_02_sfnt_off0000fc1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC1B 17620 bytes
SHA-256: 58fb43def044327c53a24fb521d5d90bddb626ed675d5f6b8daba624260803ed