Malicious PDF — malware analysis report

Static analysis result for SHA-256 f517b4bb662d036c…

MALICIOUS

PDF

76.7 KB Created: 2021-09-21 01:58:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4dbdfa9d940c5076af1b5467d31987b8 SHA-1: 023641d0cac6dad61c53aaf689e6b1257614d4e4 SHA-256: f517b4bb662d036cbe59c88bb17751156d7fbe19a85ac21fec284bc5d0bcb70a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS upload storage 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 distribution. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 https://oniceh.ru/uplcv?utm_term=codigo+ativa%C3%A7%C3%A3o+sygic+android PDF link annotation
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/zazobisedi.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/4757317037.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161326328ce555---13487604440.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/31061574669.pdfIn PDF document text
    • http://yuqiaohome.com/uploads/files/202109201619478605.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/tevilop.pdfIn PDF document text
    • http://klenderbio.com/upload/files/kuxepusadusezakidile.pdfIn PDF document text
    • http://jatyn.cn/upfiles/202109/file/1631106843.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/todadusopiwagugolav.pdfIn PDF document text
    • http://auroraenergyproject.it/userfiles/files/74430909453.pdfIn PDF document text
    • http://bdsductri.com/upload/files/pojoxavajo.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/13157287201.pdfIn PDF document text
    • http://oticonshop.com/ckfinder/userfiles/files/xopatixibipipesisaniwujok.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b29a34915---6879730198.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/bagerapewesubimibanoke.pdfIn PDF document text
    • http://sowa-architekci.pl/userfiles/files/15904680982.pdfIn PDF document text
    • http://mobilni-kadernictvi.cz/files/file/suzegan.pdfIn PDF document text
    • http://salonorganica.ru/upload/files/wured.pdfIn PDF document text
    • http://maezawa-jidousha.com/js/upload/files/82681188778.pdfIn PDF document text
    • https://stehovani-ostrava.cz/static_pages_files/file/43728645011.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/pizeku.pdfIn PDF document text
    • http://centralgiving.com/media/userfiles/file/13759470618.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/16146c9f911df4---fumubon.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202109130122258999.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_off0000c445.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC445 17844 bytes
SHA-256: 3324a42e29b8be2977e6364b71b11243254d8f32e01a9762692d793b3a26b9fa
font_01_sfnt_off0000f270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF270 11040 bytes
SHA-256: 0f85e21d8452dfa7e1444b9b0f56ba4d83d8aa74f2e613223d6ff7b6aa420e55
font_02_sfnt_off00010b6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1