Malicious PDF — malware analysis report

Static analysis result for SHA-256 99d297c9f754d187…

MALICIOUS

PDF

72.9 KB Created: 2021-09-17 11:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1446319caa93be58d83819af563e9299 SHA-1: 237c1ff6a69f498777d0a505f7228aa6034c4683 SHA-256: 99d297c9f754d187e8df56e00fb490e5ea8adfe980141a040866d497f80b9251
156 Risk Score

Malware Insights

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

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 potentially compromised or disposable domains. The presence of external URIs and a link farm structure suggests an attempt to redirect users to malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://dopuskvsro.ru/UserFiles/52022827828.pdf In PDF document text
    • http://373113.linker.tw/files/zoduxalumimudome.pdfIn PDF document text
    • https://careersourcechipola.com/files/public/roferirin.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/16142b603d5c69---16133608139.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614224ad19b5b---19749282127.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/34882778535.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/24688457805.pdfIn PDF document text
    • https://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/26539517798.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161417329eb654---maroveboxegoridulu.pdfIn PDF document text
    • http://terezszilvia.com/images/uploaded/file/34662823640.pdfIn PDF document text
    • http://4yoga.by/pics/files/jatufepagawix.pdfIn PDF document text
    • http://thingsantiquesla.com/userfiles/files/53854483562.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/73825293958.pdfIn PDF document text
    • https://immobiliareincentro.it/allegati/file/liwutiwubikabigixabogamor.pdfIn PDF document text
    • https://pmms-online.com/assets/file/gufolifiti.pdfIn PDF document text
    • http://suphammamnon.org/uploads/files/16582890468.pdfIn PDF document text
    • http://chinalabware.ru/d/files/93459885546.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/64d203d3de03ac2f8d09d50295b82720/17841973423.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/wodamivibuwurisivesalu.pdfIn PDF document text
    • https://asharfilalkulfi.com/ckfinder/userfiles/files/gerovojiso.pdfIn PDF document text
    • http://chieucoingason.vn/files/29241487676.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161439d05bc814---2977379641.pdfIn PDF document text
    • https://calienglish.com/ckfinder/images_store/files/penanegulo.pdfIn PDF document text
    • http://tonyprins.nl/images/uploads/file/67359979268.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=militia+hack+version+downloadPDF 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_off0000b93a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB93A 17016 bytes
SHA-256: 74f339e32fd5810b38473214b89a51e734f44d37c9edbc74fe4d81283ee2e929
font_01_sfnt_off0000e53d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE53D 10704 bytes
SHA-256: 39b66148d50c782d8a092e5434bd51af66922ece8a0b959443a9500fffe5fb9e
font_02_sfnt_off0000fdda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1