Malicious PDF — malware analysis report

Static analysis result for SHA-256 31b17ce1aa45831f…

MALICIOUS

PDF

73.2 KB Created: 2021-09-20 05:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3376074244f296302a5eea9fa0d5ed77 SHA-1: 7a45a5c27d4446653bb8aaeeee79016db9e1152b SHA-256: 31b17ce1aa45831f3824896224693c4f54ee6dd96cf421d9d854765f41285941
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised CMS uploads or hosted on disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and link farm structure suggest an attempt to lure users to external sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://musicpark-live.de/userfiles/file/dopovirogux.pdf In PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/68823781271.pdfIn PDF document text
    • http://danangsculpture.com/uploads/image/files/lexurelokokafiredi.pdfIn PDF document text
    • http://biurod9.pl/public/userfiles/file/wupoladijijawolowopoginu.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16147eb1bc9e5e---mujigedokokorogudo.pdfIn PDF document text
    • http://branonperformance.com/ckfinder/userfiles/files/xotikimuguj.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/85177163479.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021091908483022.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/32178959766.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///72545648835.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/xelexefujobikizojaj.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/36556825198.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210907_70058E2A4DC9287B.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/fapizemizekulalosowa.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/23073213105.pdfIn PDF document text
    • http://codienlanhtrangia.com/Images_upload/files/63948739028.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/ec7df9a4d9dc9bda1937ec08fae80f6d/22234232960.pdfIn PDF document text
    • http://ccsilver.kr/files/fckeditor/file/142228709161467ce65edd5.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/jevamipezugamapej.pdfIn PDF document text
    • https://vanrun-it.nl/userfiles/files/mazozatowizoretoxaxuvi.pdfIn PDF document text
    • https://baigiangtoanhoc.com/upload/files/26806197667.pdfIn PDF document text
    • https://metricgroup.it/uploads/file/lafosurap.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/161461d13a7170---jorak.pdfIn PDF document text
    • https://arhstroi.by/uploads/files/71120050384.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=fnf+apk+android+week+7PDF 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_off0000bdb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d5c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C5 16132 bytes
SHA-256: 2f55fb95abcafcbc9a3afe777d0df314d5b039478789f8d84045b076f8571384
font_02_sfnt_off0000ff6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6B 10384 bytes
SHA-256: ed73f5223e285ce3b23b4ab6ca08a6674b375d9ff914ddd5ea923ee7c852bbf0