Malicious PDF — malware analysis report

Static analysis result for SHA-256 237d3e830ad7a206…

MALICIOUS

PDF

90.0 KB Created: 2021-10-17 07:37:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 4b9d4d4d4cd4ef3070f5790fcfc91db8 SHA-1: 344c738f27686970519620adb8f3b9ab2aa5c191 SHA-256: 237d3e830ad7a20690ef671aab1d3ff5ebb948fa8279eca1c436423bcef73f04
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, 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 distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://echipamente-scule.ro/userfiles/file/zififipipakuxutam.pdf In PDF document text
    • http://solmoda.it/userfiles/files/bikelefemurazoxikalabi.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad76995afe---feritulekupogujeferalu.pdfIn PDF document text
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16162baf337971---fixumar.pdfIn PDF document text
    • https://daquin-ferriere.fr/userfiles/file/fudukerikujuvonova.pdfIn PDF document text
    • http://telangana99.com/userfiles/file/kawunuwijiforokosutef.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/15602716013.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/buvadedetizuzewoluko.pdfIn PDF document text
    • http://tcyy88.com/userfiles/file/2021101707280173499.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/161536850b2df5---49546791602.pdfIn PDF document text
    • http://maurovalleferroarchitetto.eu/userfiles/files/28925354703.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210919_9CF6FA8FEFFA3F40.pdfIn PDF document text
    • http://podlahyadvere.sk/editor_uploads/system/files/61738054333.pdfIn PDF document text
    • https://kondoreskiss.hu/term_extr/files/bomalikokagorefelirezivux.pdfIn PDF document text
    • http://deliver.cueicha.com/assets/upload/files/sepulerivowijebeb.pdfIn PDF document text
    • https://newchat.xyz/js/ckfinder/userfiles/files/74681184169.pdfIn PDF document text
    • http://thucphamchucnangmy.vn/uploads/files/jofiw.pdfIn PDF document text
    • http://directartdeal.com/uploaded_files/userfiles/files/sugovuduxikifuzuxikejali.pdfIn PDF document text
    • http://istihdamhaberleri.com/upload/ckfinder/files/55416259579.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109070915418646.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f02e1db29c---83019911398.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/42078404818.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/20979247647.pdfIn PDF document text
    • http://spellenindex.nl/images/uploads/gotuloniri.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/cmwvf4RlXg4/uplcv?utm_term=personal+success+examplesPDF 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_off0000f93e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93E 10548 bytes
SHA-256: dd3a9a5f60c6a4ef434761ace4ab831cf14db0ead55de07e68a395f8cc0f92c6
font_01_sfnt_off00011155.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11155 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12967 18648 bytes
SHA-256: de19961bbaacdc2a6f5a749423c5efd9f6608a0f989cd452e233ad498b68c77c