Malicious PDF — malware analysis report

Static analysis result for SHA-256 38311b9408fa78f6…

MALICIOUS

PDF

69.8 KB Created: 2021-09-16 16:56:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 7c305f18d7c8388fb65a8e99a3df0954 SHA-1: 3cbe430c3d96d4c74ad72e85475bf9d2bc18f501 SHA-256: 38311b9408fa78f631b1d43258625c742ef69a6ce8b46c6c8102b6c64869b4bf
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The heuristics indicate the PDF acts as a link farm, pointing to compromised WordPress upload storage and other disposable hosting sites. These links are likely intended to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161361dd9d07db---popeso.pdf In PDF document text
    • https://kozhikodedeaf.org/admin/my_files/file/64237814735.pdfIn PDF document text
    • http://flywings.sk/UserFiles/file/21990716391.pdfIn PDF document text
    • http://hp-cnc.de/uploads/files/18814501554.pdfIn PDF document text
    • http://haenuri.net/ckupload/files/mimozibofikoxozux.pdfIn PDF document text
    • http://bora.su/ckfinder/userfiles/files/pixevobefivajifuwe.pdfIn PDF document text
    • http://888chji.com/userfiles/files/getup.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132c845bd6c1---sumalopobomakoligunif.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16132cd9f264c9---sopoki.pdfIn PDF document text
    • https://btegypt.com/file/bunur.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/vogololusit.pdfIn PDF document text
    • https://karlschool.org/uploads/files/202109122245126378.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/rolagotinenubezapuzeb.pdfIn PDF document text
    • https://kocarbonag.com/luutru/files/vesodom.pdfIn PDF document text
    • https://charlesstreetvideo.com/userfiles/file/rixawavomu.pdfIn PDF document text
    • https://feldmann.pl/userfiles/file/jezogowakotemera.pdfIn PDF document text
    • https://rainbowfurnitures.com/files/files/86699376651.pdfIn PDF document text
    • http://prestopc.it/upload/file/30681191790.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138215943463---zamolobudat.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/newavaruxevipozeveza.pdfIn PDF document text
    • http://life-homeshop.com/asset/uploads/files/zoresesesososavaso.pdfIn PDF document text
    • https://poojaindiangrill.com/nbloom/fckuploads/file/jiboxuvawufakuzo.pdfIn PDF document text
    • https://atiksigorta.com/files/71793939106.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=instagram+search+viewerPDF 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_off0000b3d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3D6 14932 bytes
SHA-256: b16a03d0f59041674620bd1586c8edb43da40cbf68d01f2d1f65c01381ac9283
font_01_sfnt_off0000d9a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B9 10616 bytes
SHA-256: f6552bd1907d03f5e680a4efe494699acfe0b6c321fe94fc0150a1fd959a37a0