Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac25d7eca78be408…

MALICIOUS

PDF

83.0 KB Created: 2021-09-19 18:26:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1cdef98b6761182c7ce3d9d704a36fb7 SHA-1: af4b98f71aa95764d248b200da39ff3dd90520da SHA-256: ac25d7eca78be40862523941b9aa9a738e07afeb51e488ef856f806e4894bf25
134 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 disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the malicious nature by identifying a pattern of linking to numerous external, potentially malicious, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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://techscreening.com/userfiles/files/29607863231.pdf In PDF document text
    • https://gadd-asso.org/userfiles/file/jikanuvuzagugifefedazevo.pdfIn PDF document text
    • http://dietaltop.com/userfiles/files/nosevamepajometowegerire.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/1604206097.pdfIn PDF document text
    • https://lifecareproduct.in/ckfinder/userfiles/files/fojetetefo.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/fakojitugurelivizixa.pdfIn PDF document text
    • http://psychologadamczak.pl/userfiles/file/36086652093.pdfIn PDF document text
    • http://all-paca.com/ckeditor/ckfinder/core/connector/php/uploads/files/31418882212.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/78906575347.pdfIn PDF document text
    • http://jenistudio.com/upload/FCK/file/sunumemizuputadelufuza.pdfIn PDF document text
    • http://xn--49s538bo8ux8c.net/userfiles/file/87665386847.pdfIn PDF document text
    • https://serpavenger.com/ckfinder/userfiles/files/15173189618.pdfIn PDF document text
    • http://zgic.ru/!upload/files/94784807978.pdfIn PDF document text
    • http://furniture83.com/upload/files/88289756338.pdfIn PDF document text
    • http://jgbt.us/pds/userfiles/files/12970752165.pdfIn PDF document text
    • http://nicolalazzarotto.com/userfiles/files/dosogavetijibedaraz.pdfIn PDF document text
    • http://ubytovani-budejovice.cz/picture/vtextu/file/76251138324.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/putip.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/87171455464.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d0cb2e3d5d---18704855003.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/81208254484.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/27190255002.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/27560194654.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=best+free+photo+filters+app+for+androidPDF link annotation
    • https://grupo.iberia.com/js/ckfinder/userfiles/files/tofapoverajobobuzewawit.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_off0000e054.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE054 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f866.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF866 17484 bytes
SHA-256: dc8c85a5a257fa2bac8fe29e1528ff03a228f960a6e120754fddc04653001cae
font_02_sfnt_off000125b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125B8 10648 bytes
SHA-256: 8fe78d003e003e83e0ce7741b9f9da26e8324e79df5339e7bd61fa3520c9948a