Malicious PDF — malware analysis report

Static analysis result for SHA-256 43abd385114882c6…

MALICIOUS

PDF

93.7 KB Created: 2021-09-06 01:14:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5ad45a2077ece89f38a89049fc4955bc SHA-1: 3eb88e099eb87b49ffe202f1b8eff97ac3a091a7 SHA-256: 43abd385114882c6356b7f46c71766b48a07b7e8e13355712bc079d949825f70
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to domains flagged as disposable or potentially compromised. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for human readability but rather to host the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://alexandercdg.com/clients/36029/File/dejukev.pdf In PDF document text
    • http://brainbond.ro/userfiles/file/52937156853.pdfIn PDF document text
    • http://wonikqnc.com/upload/editor/file/1623446291.pdfIn PDF document text
    • https://travellifeafrica.com/ci/userfiles/files/vaninetimixovajabu.pdfIn PDF document text
    • http://balbu.eu/uploads/news/file/vovere.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/texuw.pdfIn PDF document text
    • http://meta-min.com/files/sudiwosokilexezuto.pdfIn PDF document text
    • http://dfwarbitrator.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/binoxamedumi.pdfIn PDF document text
    • http://domainecomps.com/documents/files/29239644484.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/zadazaronapakule.pdfIn PDF document text
    • http://novafish.it/userfiles/files/pinug.pdfIn PDF document text
    • https://thuhuonglacquer.com/uploads/news_file/84909985093.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/fogelevabag.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606ea0bcb0da9---vugemoxuziveri.pdfIn PDF document text
    • http://korean-school.hu/hangul/userfiles/file/43246025484.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/07/file/202107010220226036.pdfIn PDF document text
    • https://lompatjauh.com/contents/files/jubepip.pdfIn PDF document text
    • http://eszixv.hu/ckfinder/userfiles/files/nixawatonesibijoriveko.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e26782e07b---gevedefetunugepupunusufiz.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/nbf71fbqdtkdu4ssnjj7p1bqim/gugupox.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/5871385456dca022baa4b4e72a6d5a1b/99203979518.pdfIn PDF document text
    • https://firsatoyun.com/calisma2/files/uploads/58815991394.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/a190caa768728fa724d6c484984fe3a9/11549843181.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160dbbb9c78058---kufukujuposozi.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/161078b745a00e---90821218298.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=mathematik+verstehen+2+l%C3%B6sungen+pdfPDF 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_off0001034b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034B 19276 bytes
SHA-256: 63857e84a8498fafc8c6857e72006f7843771de187c995924098ac2f9a17e05d
font_01_sfnt_off0001345a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1345A 11412 bytes
SHA-256: c54ce7bc4499b38362758394583f916365e0f8204e910716061db90509cc5190
font_02_sfnt_off00014edc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EDC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1