Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9d833476b7243bc…

MALICIOUS

PDF

82.9 KB Created: 2021-09-13 16:52:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 6c85bacdf3707f8e2ec86a9430007668 SHA-1: b0701ffc8953528d5cc0ae059bb4f6feecce7ceb SHA-256: c9d833476b7243bc55e00a7363a702ca2946de0d9f812f985b22ec6cbfc0dbdb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://uspeh-kursk.ru/ckfinder/userfiles/files/78542411915.pdf In PDF document text
    • http://coming-c.com/userfiles/file/tafodulivisodipotu.pdfIn PDF document text
    • http://a9188.com/upload_files/art_files/files/20210910_171203.pdfIn PDF document text
    • https://privatecambodiatour.com/userfiles/file/90699632498.pdfIn PDF document text
    • http://asid.rw/userfiles/file/84239073222.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/5390228597.pdfIn PDF document text
    • http://bfcy88.com/uploads/files/povujefixilosobod.pdfIn PDF document text
    • http://vegasoft.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161371c2cccf18---30397912527.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/f99b3e5952498b432f5291360c9a74a2/50757100835.pdfIn PDF document text
    • http://nc-israel.ru/upload/files/84647204702.pdfIn PDF document text
    • http://gold-carsales.com/js/upload/files/22599699550.pdfIn PDF document text
    • https://vpmemorial.net/images/file/4078432758.pdfIn PDF document text
    • http://w.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/lexomukoxavegef.pdfIn PDF document text
    • http://stfurnimart.com/file_media/file_image/file/selinamuxozoge.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/83600909974.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/mutovadojijebu.pdfIn PDF document text
    • http://unseenadventure.com/userfiles/file/pulofanotizolitovebos.pdfIn PDF document text
    • https://akgoz.zemta.com/uploads/files/kuwavolimekadapojukixogi.pdfIn PDF document text
    • http://schodylux.pl/userfiles/file/79197993955.pdfIn PDF document text
    • http://kirakuramen.com/uploads/files/sotaxarav.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/5f540580d84dda04c2729207662ac544/foluwibisosemopazo.pdfIn PDF document text
    • http://phukiendoxe.com/media/ftp/file/pibosudizipuf.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/liluwun.pdfIn PDF document text
    • http://52963566.com/upload/file/202109091936006314.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=444+meaning+law+of+attractionPDF 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_off0000de16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE16 10580 bytes
SHA-256: e2e6ab6b0b2b95da47c76b6396189b88251a9b8fda751e0adf443466fdef4c10
font_01_sfnt_off0000f63f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF63F 18472 bytes
SHA-256: f15eb7e882396e853d919f5016501c0f5a182cff69d285912abadc6ae85a2a07
font_02_sfnt_off000125fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1