Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a80f430b05e8a58…

MALICIOUS

PDF

72.3 KB Created: 2021-09-10 21:11:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ca1510b5ea5aecef8e876102d35fb388 SHA-1: 3d187261d62bc7d8b4d561ea607702e70c376348 SHA-256: 4a80f430b05e8a5811dc09f30cc03221550f707f9c8645c59c8aeb106198f5e4
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads or disposable domains. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous links strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://jar-ted.pl/file/gowabafopug.pdf In PDF document text
    • http://nuovojob.com/userfiles/files/37276933661.pdfIn PDF document text
    • https://uslugiinzynierskie.com/eurostyl/photos/file/67942096949.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/50280497037.pdfIn PDF document text
    • http://xn--oy2b9bv81anouola.com/upload/file/202109082346419636.pdfIn PDF document text
    • https://ancoraeducacion.com/images/nugejetotojive.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/67f7a5128a9f10c541166e45ed59e04a/54816101015.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16132669b27ee9---85156686872.pdfIn PDF document text
    • http://indecomavo.pl/userimg/inc/vopesutozenozepazewepotug.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332bd58b5f2---popoviweloferus.pdfIn PDF document text
    • http://kondicionery-fryazino.ru/upload_picture/file/taberudazuwelosugowa.pdfIn PDF document text
    • http://krukaiart.com/userfiles/files/bofupabolon.pdfIn PDF document text
    • http://stamforgtechnologies.com/uploads/libaxudo.pdfIn PDF document text
    • http://xn--80aaa1acmiejxr6d7fg.xn--p1ai/data/files/28841131010.pdfIn PDF document text
    • http://wawa757.com/uploads/files/nufovelat.pdfIn PDF document text
    • http://tacchigroup.com/public/thread/risorse/file/71783763251.pdfIn PDF document text
    • http://kepco-group.com/uploaded_files/userfiles/files/megibofadiniwutupese.pdfIn PDF document text
    • http://fusiongrup.ro/userfiles/file/71714946126.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/robasinifipepuximiw.pdfIn PDF document text
    • http://shangyi-pump.com/uploads/file/081111135204.pdfIn PDF document text
    • https://protrialse.eu/files/files/milimorinoda.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=bar+chart+distributionPDF 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_off0000ba26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD238 16324 bytes
SHA-256: a5f34c285917f0a5f7aae617f5453ef5b600d8c056bd3be3d6b97265649fbd97
font_02_sfnt_off0000fc20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC20 10580 bytes
SHA-256: 4c7a8498ac2bab5dbbf28d7b7ad467774ce95027fda199d59b004bc2d37a677f