Malicious PDF — malware analysis report

Static analysis result for SHA-256 b82bd9a68de11934…

MALICIOUS

PDF

83.7 KB Created: 2021-09-15 11:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: b41d84b63a17cdd6d6102097a933e0f6 SHA-1: 8904afad75e3b8a8aa56ea02be6c9d97f071f001 SHA-256: b82bd9a68de11934a5d60f57b96c7c2909a57fc05b3a47223e52c19f21d87a04
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and multiple external URIs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript stream is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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://bjavc.com/filespath/files/20210905133342.pdf In PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138664c529e3---43404622886.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/munesinum.pdfIn PDF document text
    • http://rdasesores.gestconcursal.com/editor/ckfinder/userfiles/files/48559542836.pdfIn PDF document text
    • http://pilanatofishing.com/home/sandbox/domains/shelter.sandbox.tritek.hk/public_html/ckfinder/userfiles/files/18329905385.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/41959326735.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161386632d2f69---89106868603.pdfIn PDF document text
    • http://gazduire-domeniu.com/UserFiles/file/saxofuvifukixibuxi.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/86484398713.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/duguxiguradikokul.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130232428f88---tovudajoxakov.pdfIn PDF document text
    • https://12tiga.com/contents/files/kibokuwojedow.pdfIn PDF document text
    • http://grimastone.ru/files/85723765460.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/vamolesapufuraxenelokanop.pdfIn PDF document text
    • https://dptech.vn/uploads/files/37760704906.pdfIn PDF document text
    • https://www.temtechnologies.fr/ckfinder/userfiles/files/bejupug.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/50222211173.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613390a223ab5---38395150429.pdfIn PDF document text
    • https://mimpishio.com/contents/files/36219026102.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/sudadajetofikozi.pdfIn PDF document text
    • http://landonintergroup.com/ckfinder/userfiles/files/42205348212.pdfIn PDF document text
    • http://merklink.nl/site/data/ws/files/45738716424.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/66270766129.pdfIn PDF document text
    • http://viacaosaopedro.com/www/js/ckfinder/userfiles/files/53795593363.pdfIn PDF document text
    • http://satyavnetworks.com/fck_upload_images/file/5509793020.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=mi+game+booster+apk+downloadPDF 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_off0000df88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF88 11044 bytes
SHA-256: b5bc7899cdb41e8711ce75d0267b1cd7f6db1629ca2a1f69b6790b9243fd39f0
font_01_sfnt_off0000f8e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110F6 18092 bytes
SHA-256: b956593f66283e952ee32d999b9dcd3279088239acb07c0f8415549404138a28