Malicious PDF — malware analysis report

Static analysis result for SHA-256 121615749bb11438…

MALICIOUS

PDF

73.2 KB Created: 2021-09-02 07:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 15f40ade25c42c92fd3e0e527f7f5ba9 SHA-1: 48bbbb266671cbf78b48c0364bdec4688f4e9874 SHA-256: 121615749bb1143805e047e735f36859bf60452b93a0de2d67113a73870d9cff
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a significant number of external links, many pointing to compromised CMS uploads and disposable hosting, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis are sufficient to determine its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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.
  • 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://kaies.cn/upfiles/file/wovipijasupalatikowixaxo.pdf In PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082cb92a2ec6---56349819865.pdfIn PDF document text
    • http://zamel2.pl/userfiles/file/lonexowenupibonejujosediz.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6934f3a4f---39977348340.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbc4d11bf4---79166443110.pdfIn PDF document text
    • http://armanetti.com/images/10498680711.pdfIn PDF document text
    • https://ldcpc.com/ckfinder/userfiles/files/tazuwopajabikitimix.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/c76u321dqb866f1m60pqu7f1fk/fejekunituxovuzud.pdfIn PDF document text
    • http://tangiahoang.com/skinkorea/Images_upload/files/33906298143.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/jofinukajixosunuta.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075a79580574---41791448479.pdfIn PDF document text
    • https://arerp.kr/data/file///62865038445.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/52785580430.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cd4da3af86---1206113898.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/7c92e77ef68ef2ca585e5e6b3a9b8727/94614559460.pdfIn PDF document text
    • http://grawerlik.pl/userfiles/file/geritinogasidelenomubaxi.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/glhk2ftdjtprmftfng3v31drpp/pebewutiwugulu.pdfIn PDF document text
    • http://positiveforce.in/uploads/files/xedaraputefude.pdfIn PDF document text
    • https://pasarantogeldua.com/contents//files/85740440617.pdfIn PDF document text
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c92e7e4d36d---48490007501.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/62660473753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=drives+in+electricalPDF link annotation
    • 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_off0000b839.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB839 10168 bytes
SHA-256: 25bb9e96a87714db9ffd795130ba73c9a649cb99cdc9b1fbbac2c390b879b8c1
font_01_sfnt_off0000cf2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e73c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE73C 17780 bytes
SHA-256: e5fe473aae8414e3a454ab406fa771857484ee02b45ff77fac17b503d17a9d64