Malicious PDF — malware analysis report

Static analysis result for SHA-256 3968a57cb78c8d7f…

MALICIOUS

PDF

80.8 KB Created: 2021-07-24 00:35:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 71feb7e8980d2780dd4fbbb92797dd25 SHA-1: 7a8f39f2bf8bad0ba75e6312082aec65478c89ba SHA-256: 3968a57cb78c8d7f631cfe17fc8081effae58c3cc5c6536add5f05ac5d99325b
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads, suggesting it's designed to redirect users through a chain of potentially malicious sites. The presence of numerous URLs, many hosted on compromised WordPress sites, reinforces the attack pattern of using link farms for obfuscation and redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9941

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
  • 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 https://www.medipratik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad8c2b45c90---43174879320.pdf In PDF document text
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/v8uq91t2vi3btudj3f04jd7tap/tajenizebewewufej.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/59171535187.pdfIn PDF document text
    • http://azizavacanze.com/userfiles/files/xavepotamifosam.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607cca5da7ce6---94620775509.pdfIn PDF document text
    • http://adhdesign.de/userContent/files/20210621025935-71720411474.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/15588582059.pdfIn PDF document text
    • http://barnesfamilyre-union.com/clients/52050/File/55982135776.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160d85731da71e---zevazuparini.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/movixerix.pdfIn PDF document text
    • https://pharmnet.cz/ckfiles/files/files/74979911766.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16085a6afb9487---49909027214.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/m022apchegen0um5baukf6m0b3/19918503378.pdfIn PDF document text
    • http://mini-garden.ru/userfiles/file/22647359927.pdfIn PDF document text
    • http://alexandercdg.com/clients/36029/File/87089574005.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/dugulimigolutawi.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f1ab1afdf---18993716743.pdfIn PDF document text
    • http://w-w.cn/isee/pfm/cms/uploadfile/fck/file/93634392107.pdfIn PDF document text
    • http://stardentalcare.org/userfiles/file/poxejosofadanu.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/52fe962dee9c48a3939c7702b12f5a85/muvudalojomufekuzix.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c41cb4ec1ed---perewejemoruru.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160847891b2f2d---54657717368.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/gp05a0956h15m2jm9r8opabi0r/xiwezoba.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/oonq5hm5b3tlnl70a1anbip672/vebokuvifomekabol.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/12a295ad1cacfee6950063150a0cb7b1/90626073155.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/c78202111225648045c494a660b700a3/76187309985.pdfIn PDF document text
    • https://menu2uplus.com/images/file/55061014010.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=cuadernillo+de+matematicas+sexto+grado+de+primaria+pdfPDF 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_off0000d46f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD46F 11196 bytes
SHA-256: cf66cbdbc2b99ee2248492d099a924caf88a20f1a25288ad5af3180f783f1171
font_01_sfnt_off0000ee6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6A 17612 bytes
SHA-256: 463f82b8132b3e372fd46d7bc5f8c2659458242d39757d50b26b11134f493200
font_02_sfnt_off00011b03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1