Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d5b3da450444cba…

MALICIOUS

PDF

79.0 KB Created: 2021-09-24 11:24:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 80bb13a5449c417df25cecc3c5860946 SHA-1: 0534cee7e1e0c652d35ae564c918edfcfe020e54 SHA-256: 8d5b3da450444cbac9e22eb70cbe07390f03998b0c606a937805882d438935a0
164 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous URLs, many of which are part of a link farm hosted on compromised WordPress sites and disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish users or distribute further malware via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://catamma.ru/uplcv?utm_term=best+icon+launcher+for+android PDF link annotation
    • http://okgwa.net/50/files1/file/vejimadijilinafajajagaz.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141dd924aa2c---16528428640.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/lurinegag.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141eaa702f52---22113879945.pdfIn PDF document text
    • https://kalendarz.probik.pl/fckeditor/userfiles/file/31572535326.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/92146133566.pdfIn PDF document text
    • http://labmansour.com/app/webroot/js/ckfinder/userfiles/files/40212538131.pdfIn PDF document text
    • https://ms02bet.com/contents/files/66039643356.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/pobelejeninu.pdfIn PDF document text
    • http://foreverymuslim.net/home1/forevev3/public_html/foreverymuslim/upload/file/bolajipesebukig.pdfIn PDF document text
    • http://adgroup.co/userfiles/file/letesixokutawonizizise.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/wojovoguzidagese.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16137704aec40e---wufavixinosanixokotobagiv.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/48641591469.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/zifekijevigiv.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/8811345970.pdfIn PDF document text
    • http://capitaloffice.pl/fotki/file/fitenogowaza.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/60921098512.pdfIn PDF document text
    • https://bimetoor.com/basefile/bimetoorir/files/98417234409.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/kemukelojoligekuluraxaben.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/53808166306.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/65430250068.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/3d97e92b59b55a854aa04b01e0df7207/26818608771.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_off0000d309.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD309 10724 bytes
SHA-256: 5ca5888e394322b1159e3f81af33aeeab69c878f70b1e55a18566db1f4fff4dc
font_01_sfnt_off0000eba0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA0 16788 bytes
SHA-256: f8838bca926b761ff83fa8b93d55abf4174d45779c087cdafb8134f518d7d238
font_02_sfnt_off000116c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1