Malicious PDF — malware analysis report

Static analysis result for SHA-256 b42d8232a88af593…

MALICIOUS

PDF

72.0 KB Created: 2021-09-26 19:55:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0eff8a4f0db4a61de0fea9749f865a2e SHA-1: e686c64544fa31fb07a07ca90da54ffdefd6aee5 SHA-256: b42d8232a88af593563043172126dab4276e30c80b2b3cc6612db7ffad89e11d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. While no scripts were directly extracted, the nature of the links and the detection suggest an intent to redirect users to malicious sites for phishing or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

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://bharatdarshan.net/rgroup/ckfinder/userfiles/files/15383666522.pdf In PDF document text
    • http://bociany.sk/media/file/47949045987.pdfIn PDF document text
    • http://transcash.com/ci/userfiles/files/4724905276.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/87673867198.pdfIn PDF document text
    • https://onecre.com/images/content/files/watenibefugedarebi.pdfIn PDF document text
    • https://saunadlaciebie.pl/userfiles/file/ruzalovori.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/foperoti.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c74056533a---27319421784.pdfIn PDF document text
    • http://reedxtrainternational.com/uploads/pages/file/zapatosi.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/c74e31e57c1d36a5077ca06b16f45728/45532044237.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/zasubewibabawopinun.pdfIn PDF document text
    • https://nstyapi.com/resimler/files/95581036397.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/88771696086.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/85716807560.pdfIn PDF document text
    • https://webbsoil.com/home/webb/public_html/ckfinder/userfiles/files/63935180019.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/19700895727.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16145bf8397444---sufede.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/jilid.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/dariwipaturo.pdfIn PDF document text
    • https://srinivasagroup.com/ci/userfiles/files/kujavijisanelu.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/6905059389.pdfIn PDF document text
    • https://motoralbini.it/files/file/25848301103.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=name+the+most+populated+country+in+the+worldPDF 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_off0000b504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB504 11056 bytes
SHA-256: 2e804f7348e3e67e5dccef633cb18b358346e55f94327895819fcbccb9de58f7
font_01_sfnt_off0000cea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BA 17208 bytes
SHA-256: ff6dd283187b1fd63319452d097baaeb58e02d25a6b71140bb0303fc4998de9b