Malicious PDF — malware analysis report

Static analysis result for SHA-256 c97ab7734b6cbe79…

MALICIOUS

PDF

72.9 KB Created: 2021-09-21 12:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5eb16717c1f33657235d3c2c3eb01410 SHA-1: 85b9d0a330fb86199447d2a1b02911db2a3f9184 SHA-256: c97ab7734b6cbe79b9adcaf52d5f43dbbec5933c71e478519746f65d976860f7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users to potentially malicious sites. The ClamAV detection and ML classifier strongly suggest a phishing or malware distribution intent. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://cructi.ru/uplcv?utm_term=story+with+collective+nouns PDF link annotation
    • http://nhatrangpalace.net/app/webroot/upload/files/29690987113.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/zarisetupakilosuzenove.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332fd83e517---tusugadiraziz.pdfIn PDF document text
    • https://red-adlay.com/upload/files/mumobufamosemonotilowot.pdfIn PDF document text
    • http://0932018255.kad.tw/kads/ckfinder/userfiles/files/57586791754.pdfIn PDF document text
    • http://spielundlicht.de/content_provider/documents/files/41559670121.pdfIn PDF document text
    • https://eko-briketes.lv/userfiles/files/zusuzitekit.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16143a77865b79---73087242272.pdfIn PDF document text
    • http://ubest.ru/images/file/funigapexu.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16144b215489c1---72558256357.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/12584003927.pdfIn PDF document text
    • https://beeshark.ro/app/webroot/files/userfiles/files/larewokisipe.pdfIn PDF document text
    • http://80tner.netsociality.com/upload/files/faxunatilixap.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/93283113873.pdfIn PDF document text
    • https://wct.goldcrownresort.com/magazine_files/files/wilefozojefeg.pdfIn PDF document text
    • http://bouwbedrijfbouwheer.nl/userfiles/file/39955754693.pdfIn PDF document text
    • http://oris-am.com/editor_up/11461053740.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/81034426307.pdfIn PDF document text
    • https://pastravariaizvoarelebratiei.ro/images/file/89405037923.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/93955964703.pdfIn PDF document text
    • http://cottoneauto.it/userfiles/files/74400940833.pdfIn PDF document text
    • http://mcap.cz/images/uploadedimages/file/53177494203.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_off0000b999.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB999 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1AB 17336 bytes
SHA-256: 34f249d69c23f8e802ffe1c73ee9c755901206f2e26bb2d1e843e35f71d7e2e1
font_02_sfnt_off0000fe4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE4A 10604 bytes
SHA-256: a596ad466da9e41483390e2402976261b16460769e9d9261fcef442eb7a0c69a