Malicious PDF — malware analysis report

Static analysis result for SHA-256 683c2b83723e9b3d…

MALICIOUS

PDF

78.5 KB Created: 2021-09-06 10:16:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 108dd34601f8a6de71ce30cf0fcb7865 SHA-1: 9081f556c2f475892259f462f6fa576e6104a576 SHA-256: 683c2b83723e9b3d30bc3aa0618babca0730bcb8e42eac96d5cad28fba95b50b
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://seataclightingalaska.com/wp-content/plugins/super-forms/uploads/php/files/57165864e1e36bd7ac459f1435d4a0fb/70048328081.pdf In PDF document text
    • http://africanhairbraidingsalon.com/userfiles/file/46406722671.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1608eefd00114c---64364729394.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/veroso.pdfIn PDF document text
    • http://yanartextil.com/firma/files/2427329604.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/boraw.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160accf8c5980a---foresebawinevugipi.pdfIn PDF document text
    • http://xycrusher.com/d/files/davudopapovowerax.pdfIn PDF document text
    • http://kvbm.org/pds/userfiles/files/motazarexevalesavobibinel.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/gp327m7qffbjoljdmp9k2n9a9b/75648907803.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/a2a8d3a41caf57e6908f08ec1cc56cd2/nurobuni.pdfIn PDF document text
    • http://kesherisrael.com/uploadEditor/files/71309894535.pdfIn PDF document text
    • http://hodori247.com/uploads/files/jikukafivepugunuvave.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/favelobobalomuzuvobukon.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/853879920.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613573d187357---tosogakal.pdfIn PDF document text
    • http://xn----ctbguteehkho5h.xn--p1ai/ckfinder/userfiles/files/60749973206.pdfIn PDF document text
    • http://novafish.it/userfiles/files/xubalodid.pdfIn PDF document text
    • http://poorclarescork.ie/images/29612792133.pdfIn PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/jafugujevadu.pdfIn PDF document text
    • http://donghotam.com/luutru/files/xigofuxo.pdfIn PDF document text
    • http://ctmmaximoravenna.com/ckfinder/userfiles/files/fupodotizerunoradasu.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b956d79f0c---ranude.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/1609efa5f08476---lexororedesibi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=digital+signal+processing+in+matlab+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_off0000ccf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCF5 11104 bytes
SHA-256: 94d7cf6c03e16150b4959180c98f0f823179d0d477e8ddbffe03e60612af4c1d
font_01_sfnt_off0000e669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE669 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE7B 17720 bytes
SHA-256: 6eae8254e97e18b098f33c1424f93246776b4d277f840d8559e4d08dc2ead3fb