Malicious PDF — malware analysis report

Static analysis result for SHA-256 8618abd3da129e98…

MALICIOUS

PDF

72.9 KB Created: 2021-09-13 09:38:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1ae1e48ae79468af2057cc9c0179ada5 SHA-1: 04a436e56a20ea08d90ce8be5ec1911209789748 SHA-256: 8618abd3da129e98d6ddbb5bc74143f2697d648837361d875013b19db4fd62fc
156 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple PDF-specific heuristics related to URI and link farms further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://upservice.expert/admin/ckfinder/userfiles/files/wijeni.pdf In PDF document text
    • http://svx.su/ffile/file/wuxugenalusozidumiperer.pdfIn PDF document text
    • http://boxerdapolenta.com/cmsimple/images/file/59164163368.pdfIn PDF document text
    • https://groupunsur4.com/contents/files/vinoforovajegijero.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/k5112q7odu7vqa12cd29lhtb7f/zazaparozotifemixagugino.pdfIn PDF document text
    • https://12shio3.com/contents/files/jisagulakefubuj.pdfIn PDF document text
    • https://suprizpin.com/calisma2/files/uploads/89806451461.pdfIn PDF document text
    • https://villadorottya.hu/uploads/frontend/files/rutek.pdfIn PDF document text
    • http://odontoflash.eu/userfiles/files/bukotuleduneratonixapasa.pdfIn PDF document text
    • http://lianbang123.com/uploads/files/202109070023485459.pdfIn PDF document text
    • https://thehouseproduction.net/file/wopuxodokaxaxuwuse.pdfIn PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/09/57821573209.pdfIn PDF document text
    • http://whatcanidoforyou.eu/publish/file/gemivexavafixolitegixo.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/lujiwefut.pdfIn PDF document text
    • http://fisioterapiasuzzara.it/userfiles/files/22675596100.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/33b9a9f74768573fe2a9c2c98785049e/lebiwowidatuvuvuzowamiwu.pdfIn PDF document text
    • http://ff-engineering.com/userfiles/files/79833735712.pdfIn PDF document text
    • https://artistprasanna.com/userfiles/file/lajixaluzerewora.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/30542460603.pdfIn PDF document text
    • http://alkanboya.com/files/file///48632331042.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3eb6823fa---43326877501.pdfIn PDF document text
    • http://potlista.com/file/files/4568287406.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/62415891558.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=ipvanish+mod+apk+2021PDF 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_off0000bb52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB52 10684 bytes
SHA-256: c5a9396bfa8ce3c164ec4b69447ff5a267b4cad4e85fbf5125063a0aa17478e9
font_01_sfnt_off0000d3a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A7 16492 bytes
SHA-256: ccda7ee36e11b4007d6f23f8b89307240b0beee8e837489ea99cccfe50b5235f
font_02_sfnt_off0000fe07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE07 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1