Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9aa92fb5380652a…

MALICIOUS

PDF

78.0 KB Created: 2021-09-13 13:58:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 5cbab081ddab29503f008feca938ed64 SHA-1: 4e825599ca619ff96718c665a26beb73106ac62b SHA-256: a9aa92fb5380652a8254a8c265fbab513d942ac68800bdada98c30fcdb4f41fa
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 websites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://unsersohn.ch/images/file/timopabegeledisad.pdf In PDF document text
    • http://agro-pasz.pl/ckfinder/userfiles/files/58967476389.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/rebukizixevib.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/oom0gfde88tib9jumba9lbkbl0/guranagewamikufeponikaba.pdfIn PDF document text
    • https://farmaciasacoor.com/site/upload/file/34415397696.pdfIn PDF document text
    • http://lawngo.net/fckfiles/10048085826.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/kuxadifoxaxixikisiza.pdfIn PDF document text
    • http://www.hermosabeachbungalows.com/userfiles/files/5391140924.pdfIn PDF document text
    • https://deltaguvenlik.net/userfiles/file/jelazawazotegeruxak.pdfIn PDF document text
    • http://mcutech.net/upload/2021/09/file/1631257900832942765.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/nifagizekijazixuxuz.pdfIn PDF document text
    • http://tageedesign.com/ssmpt/documents/file/16719041393.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161315a95667e8---62640877346.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/57486186121.pdfIn PDF document text
    • http://bukvoznaika.ru/ckfinder/userfiles/files/futalawo.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/lldmknocbkagt55uprj24436t7/35346628497.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/94057829855.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/damimakaziwakebetuveta.pdfIn PDF document text
    • https://aldurra.ly/images-editeur/img/file/46231050833.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/23049335641.pdfIn PDF document text
    • https://uudanbury.life/files/file/papometuwuxuvamumamiwo.pdfIn PDF document text
    • http://gtlitalia.com/userfiles/files/futobanogulubidini.pdfIn PDF document text
    • http://modulobase.com/userfiles/file/tinesidemusizijato.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/65160838205.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=why+are+my+texts+not+sending+androidPDF link annotation
    • https://tes-sys.com/uploads/ckfinder/files/20210908/16310630817517.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_off0000cc76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC76 10856 bytes
SHA-256: 8c92226fe71f5860435e7b5f2d7a2d538c860134a227a3b7d5fd48c68ffdec6c
font_01_sfnt_off0000e536.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE536 17492 bytes
SHA-256: 242da62c40116c753de595b7c798d2ea26077b0137a9045da1b7c8c5e3de451d
font_02_sfnt_off00011258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11258 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1