Malicious PDF — malware analysis report

Static analysis result for SHA-256 e79743fdbf264e7a…

MALICIOUS

PDF

71.4 KB Created: 2021-09-13 12:11:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 68c0cc233d4a54b91e6f3fa9f450a593 SHA-1: 8a66b0257af511b4dbd1d4bfb08afecd2b218319 SHA-256: e79743fdbf264e7aa4f23d75d95fc1cafd8c42dce1df6260c76a8526bebccd5c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, suggesting an attempt to host malicious content or redirect users to phishing sites. The ClamAV detection and ML classifier strongly indicate malicious intent. The presence of multiple link farms and compromised hosting further supports a phishing or malware distribution attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://samocvet.org/foto/ck/files/vivimug.pdf In PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613180fbd92a3---dewowes.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/161360eab037ca---katazozuwi.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/75d1f562b35acd94eb8be9cfc0965bf6/nuvigufosoxoxezotage.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/sapajizurevofelu.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/fezebelovatoxekudi.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/lpdhp1mvcn9c3prcj9um3hdmf8/rigagod.pdfIn PDF document text
    • https://asiquim.com/ckfinder/userfiles/files/jifuvanufisivaxuturekejip.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/jawuvolop.pdfIn PDF document text
    • http://xn----1-6cdapb2bdyqawnpcindqfc.xn--p1ai/media/file/redajumibapumeguzoxuxi.pdfIn PDF document text
    • http://frangarcia.eu/upload/file/lufuga.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/91110195733.pdfIn PDF document text
    • http://chanhbon.vn/media/ftp/file/48512374241.pdfIn PDF document text
    • http://sure2trips.com/bot/ckfinder/uf/files/nijebexiwonivaxixafigi.pdfIn PDF document text
    • http://achwvs.love-mrt.com/upload/files/parelowim.pdfIn PDF document text
    • https://suadienlanhhanoi.net/upload/files/sodugebekudujovinabus.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/10468159404.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613e9bfd2cf02---jukuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=my+son+birthday+loading+imagesPDF 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_off0000b6ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6AC 10944 bytes
SHA-256: 334963275fff6e29ca5dffba73931555440daf864d61ebfdfb883a7772a0c354
font_01_sfnt_off0000cfa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFA4 16140 bytes
SHA-256: 76ea5d933c829ebd4e02ea47d406221d0dc9f728381f805c5bd2ce7ceb3c004f
font_02_sfnt_off0000f8dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1