Malicious PDF — malware analysis report

Static analysis result for SHA-256 a38679188e509c56…

MALICIOUS

PDF

98.2 KB Created: 2021-08-22 11:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 414c365cafe5b7cfaaf555265c9b891f SHA-1: afda4b3d449c3a3ea7f75918113032089c9fd376 SHA-256: a38679188e509c56becf5ae4b3468e5dd64049f05492ab446dff63e3c6ace74a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is being delivered via these links. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond the presence of these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9979

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=howard+miller+clock+chimes+at+night PDF link annotation
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607abb83b1506---dusosalamaxewurikugor.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161183699104b6---rubevu.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/86337735207.pdfIn PDF document text
    • http://kyanite.tv/userfiles/file/daliparazekubaliramubup.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/70393487941.pdfIn PDF document text
    • http://mertlakustika.cz/images/pages/file/25720418809.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/toruwubejo.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/retobi.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/40403477507.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/16073fa28b2738---10515953670.pdfIn PDF document text
    • https://fajndoktor.cz/images/file/files/wewefu.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16081b3799f268---jomamidanudukuwidakupopa.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2f111f1cb6---sewenepixoforavuvoniva.pdfIn PDF document text
    • https://gberwanda.com/gbe/useruploads/blogs/files/57676878198.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/9a31b11cc6f3fa67f113c410dc4a7b2c/wanapuzewolar.pdfIn PDF document text
    • http://ktcz.eu/files/files/72786481700.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/79466105412.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3e07b895d436cfd046e939a4ace84119/zikikukiguxosagofik.pdfIn PDF document text
    • http://ave-france.com/pics/files/visozajavim.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5926c14fc5---mewolatimilegin.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/nuzoxeginitikokitolove.pdfIn PDF document text
    • http://www.polni.si/Images/files/83497108441.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/3876324648.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/41896014305.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/jexew.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_off00011d50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D50 10984 bytes
SHA-256: f6a0cd22eba0ee5e4c81949cd3365d1f04d3d54eaa28eefb7c5a0384e14cef59
font_01_sfnt_off0001366b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1366B 16940 bytes
SHA-256: 809d572c3a16150be9f31f0309aeaace8a6042442591dd2bcd38ba7eb5786b6b
font_02_sfnt_off00016230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16230 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1