Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a8ba3b686bb9c49…

MALICIOUS

PDF

80.8 KB Created: 2021-09-14 15:49:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 470ee1633ba3776de4ec26b71f26cd58 SHA-1: 33819e412e88e4873435aed7a7a2b4fb866b25ba SHA-256: 1a8ba3b686bb9c49856563d7029df2eeea1a0a389b3bbfe2be29385d3314bea8
134 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, many of which are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://crewmak.ru/uplcv?utm_term=advanced+english+grammar+test+with+answers+pdf PDF link annotation
    • http://hepiran.com/cache/fck_files/file/97752533581.pdfIn PDF document text
    • https://kawanmto.org/contents/files/33721282764.pdfIn PDF document text
    • http://freetourscadiz.com/ckfinder/userfiles/files/dotisinifuvibo.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/gesowugovek.pdfIn PDF document text
    • http://stroyvodservice.ru/upload/File/rotedipavepogido.pdfIn PDF document text
    • http://worldtile.net/jangheung/userfiles/file/57090607448.pdfIn PDF document text
    • http://pastoret.it/userfiles/files/dibadazavefusenosevamam.pdfIn PDF document text
    • https://linlinline.biz/js/ckfinder/userfiles/files/dulogegeruvipokudifovazaw.pdfIn PDF document text
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/subesewuw.pdfIn PDF document text
    • http://hightopeducation.com/cms_uploaded/file/sanivevoje.pdfIn PDF document text
    • https://meganimal.pt/site/upload/file/59078682934.pdfIn PDF document text
    • http://mos-craciun-inchiriere.ro/fckfiles/file/depijipomenitabemi.pdfIn PDF document text
    • https://avflash.nl/upload/files/xironetekoxaliredeku.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161305fa8c303c---76026426993.pdfIn PDF document text
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/80491255715.pdfIn PDF document text
    • http://unitekinfostructures.com/userfiles/file/30971026050.pdfIn PDF document text
    • https://nedimgame.com/calisma2/files/uploads/24468170433.pdfIn PDF document text
    • http://rentappli.com/tinymce/jscripts/tiny_mce/plugins/phpimage/phpimage/upload/images/file/wovexoseradenilu.pdfIn PDF document text
    • http://bndweb.nl/upload/files/30576605144.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/13452076072.pdfIn PDF document text
    • https://arnetbilgisayar.com/upload/ckfinder/files/dabutabobijomaroz.pdfIn PDF document text
    • https://mimpishio2.com/contents/files/36776574842.pdfIn PDF document text
    • https://aokman-drive.com/d/files/90092308128.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/kemofe.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/61973075174.pdfIn PDF document text
    • http://szybkieprawko.pl/szybkieprawko.pl/user/admin/fck/file/69368043700.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_off0000d447.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD447 18180 bytes
SHA-256: ac538901e909920529cbf988cf79d3c6ddf645822e8743fe2f553b3764a45877
font_01_sfnt_off00010392.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10392 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BA9 11080 bytes
SHA-256: 1ae46b02bbab065f6e7dd65517b23d691b479e070c801736bcc6323fc7ddbc7f