Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b242ce4a369be8a…

MALICIOUS

PDF

72.0 KB Created: 2021-09-01 22:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0b3932b87a43f819147739d0edfa341d SHA-1: 91649b8cdb1ec57726c64f0cc1abc0a76ff90086 SHA-256: 8b242ce4a369be8ae8aea1e0d384aca91f90c54779077a460ede1fca370c2c72
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised CMS uploads and disposable hosting, likely to distribute further malicious content or phish users. The document body is heavily obfuscated and contains no readable text, indicating its primary purpose is to host these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://archism.ru/uplcv?utm_term=easy+chicken+and+dumplings+from+scratch PDF link annotation
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6dcb2aed26---sikoturejakopinomapami.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/fjsa51ho9ghf30i0iqhembpv48/kififutogosajize.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/dabuvoripidiz.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/f05qo1kjp9u8jetpmlqmsruelf/pinepipenubipumivufez.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/jhflrpdrt1e8bpuqvqh0a8evk6/waxapizajetil.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/16076dd9cf3aeb---2166719428.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/827ab2434577e3537c173bb9ac8c2deb/babogovaka.pdfIn PDF document text
    • http://studioscoponi.eu/userfiles/files/murifixitanuwef.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/3208093406.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/vofaliniverowujob.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/kunosukegudiwiwepexepota.pdfIn PDF document text
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/d022d12cf31706eceeca0f407c0ab26a/57624155266.pdfIn PDF document text
    • https://actorconseil.com/files/file/87392004011.pdfIn PDF document text
    • http://www.gabrielamaciel.net/images/content/file/bisisepowebekumuwe.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/1263225836.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/2honkc93uaqfe6tp4pdctavr4h/sirodesokunemal.pdfIn PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/bogehoa3mnbpa6in41t1o3kq28/87368995099.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/82265886194.pdfIn PDF document text
    • https://badoza.net/userfiles/file/lobanigaxuzotobolo.pdfIn PDF document text
    • http://soles2walk.cz/data/file/jelixatimatureduvidub.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea4583f48a---norokuzowazulijasezavepi.pdfIn PDF document text
    • https://parfumzone.ro/files/file/56417540299.pdfIn PDF document text
    • http://armanetti.com/images/lomemazuvuxufawamodoso.pdfIn PDF document text
    • http://deauville.ru/files/file/98460049480.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d40a97cd339---91421988876.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7de80a128---raviwapofiketenoxitunezu.pdfIn PDF document text
    • http://boletin.alicantehosteleria.com/lib/ckfinder/userfiles/files/19436638383.pdfIn PDF document text
    • 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_off0000ba95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA95 14652 bytes
SHA-256: b73883226a101cd69b54c73805552ec7fab54ff9b93eae3a09ed69f530c22d5d
font_01_sfnt_off0000df51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f768.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF768 11356 bytes
SHA-256: 784822afe6b51a978741652418b581bef776a303858e4f3693c1f69813dfcd33