Malicious PDF — malware analysis report

Static analysis result for SHA-256 18f67bd6b959abc6…

MALICIOUS

PDF

89.2 KB Created: 2021-09-19 12:17:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8a60a65f73247c3d33e37369a4044da5 SHA-1: 184d0e61067be53d75729883c37a3974dd8b3975 SHA-256: 18f67bd6b959abc623feef07b9cfd967874766db8bc60b0cba818daf6e5686b5
126 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs pointing to various domains, some of which appear to be disposable or used for hosting malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags the document's structure as a potential tactic for distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://biondiairsystem.it/userfiles/files/96422014112.pdf In PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16142b3d693c45---pefakut.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/69277086280.pdfIn PDF document text
    • http://textstricker.de/benutzerdateien/riborupawofimopimuvekam.pdfIn PDF document text
    • http://smartvoicesys.com/userfiles/15663024984.pdfIn PDF document text
    • http://sharon-barron.com/userfiles/files/kugilivegizowujaxulakem.pdfIn PDF document text
    • https://10fci.org/userfiles/file/wujudufuwutuxibovovatef.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/56876437290.pdfIn PDF document text
    • http://bjavc.com/filespath/files/20210909170622.pdfIn PDF document text
    • http://viswinkelindex.nl/images/uploads/nolexekatezawomoxe.pdfIn PDF document text
    • http://dealershop.es/camarasegovia/userfiles/file/kudoduf.pdfIn PDF document text
    • https://martas.vodrsport.cz/uploads/files/10353334514.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/79450663039.pdfIn PDF document text
    • https://nieruchomosciprzetargi.pl/files/file/23360488898.pdfIn PDF document text
    • http://hsaltsj.com/uploads/files/23859758993.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/zosid.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/tolunorur.pdfIn PDF document text
    • https://vanchuyenduongsat.vn/upload/files/982645124.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/45968714339.pdfIn PDF document text
    • https://perfecthospital.org/ckfinder/userfiles/files/tetek.pdfIn PDF document text
    • http://oskarmak.com/userfiles/file/44112217858.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abf0127218---38928684318.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/dejavatoxotozewijajubo.pdfIn PDF document text
    • http://eskuvotoszkanaban.hu/editor_up/86893157054.pdfIn PDF document text
    • http://thuonghieutoancau.vn/uploads/files/4880744687.pdfIn PDF document text
    • http://nonstopsushi.com/uploads/files/jodizuzifapovulilas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=watch+2016+movie+online+freePDF 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_off0000f8b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B1 17596 bytes
SHA-256: ab94595ac8a8f22ada9d02e40a2d048b4829c17b720059212c94f58b1446e7b3
font_01_sfnt_off000125e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013dff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DFF 10956 bytes
SHA-256: 4a4715cc1049e7f6a150931aa088dbb502aaab66ef90c24431eb6ba4e6ae8425