Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dbcd60cd02c1494…

MALICIOUS

PDF

98.3 KB Created: 2021-06-25 12:17:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: f3a744a11ba485270ccd41ca15423480 SHA-1: fb46bc29cfdf8be94c7e886d22f41f81aad42f0c SHA-256: 4dbcd60cd02c1494b29dd4367c255c21afdd73a860928b4c3d1ce00eaad00465
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics strongly suggest this PDF is used as a lure, likely for phishing or to distribute further malware, aligning with the Spearphishing Attachment technique.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://coretry.ru/uplcv?utm_term=calculus+with+analytic+geometry+by+sm+yusuf+book+pdf PDF link annotation
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/3170926ff24cf9b8a0c02e224be8054a/limabemofofup.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/160ae0ca7e8485---91027982376.pdfIn PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b29c30d2223---siwudijubuwet.pdfIn PDF document text
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/tidapip.pdfIn PDF document text
    • https://marblobaths.com/app/webroot/img/files/xidokajaweb.pdfIn PDF document text
    • http://eau-msu.ru/ckfinder/userfiles/files/rusomarumedutuwogegoxa.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607416733922b---4217672504.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2417861728---livoromajeruxu.pdfIn PDF document text
    • https://oliogalanis.com/file/rusofuxifapikepefigurok.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/5d8b105aa570e1d248dd739afebd502b/zojovow.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/aefd361a29e83079ee0602c43164f3a9/ledit.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/9f4giin2t0r4i26udvntah93ub/zixanavirifegawul.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c20e2a0eb24---wurekopava.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/1ppcoooh8iehagug0n2s83g052/37728040206.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/zozunowukatopamuvuki.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c9329798be---59616935506.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/kidageredivuzupojoxuwug.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/9600652487.pdfIn PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/44dec9a7fa6dce7a75abc3949c7cd145/guvusulinon.pdfIn PDF document text
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831b241c711---6042644844.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_off00011684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11684 11632 bytes
SHA-256: a76b139ba6c3504a5113896264349fab6c1798bd99b25285953e8092516c039e
font_01_sfnt_off000131a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131A6 18720 bytes
SHA-256: 6d31741428f916fac41620679bdaadf0655d4c57017e573593b3a7a93cc4a7a3
font_02_sfnt_off000163a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x163A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1