Malicious PDF — malware analysis report

Static analysis result for SHA-256 b90aca71c44fe44c…

MALICIOUS

PDF

80.7 KB Created: 2021-09-01 07:59:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f4c645046bc84c35618c6af1646b988d SHA-1: 4f783a1c93111ad13236d9aec0282e60f3cd19ff SHA-256: b90aca71c44fe44c1da418c00013cbbbc563e0bc3ad79c320fe6be4a4a2f2a1e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links pointing to compromised websites, many of which host other PDF files. This suggests a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to distributing further malicious content via the linked PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16117f2c3cf829---39260169368.pdf In PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/11094063913.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210727005431_2op74u.pdfIn PDF document text
    • http://hakkabrothers.com/userfiles/file///38414468337.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d66fe9e2582---vebija.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/68028976485.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1611d41649df36---ditirosujota.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/lch0m1fgm9be8ei9k6sfghshg3/botedirig.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/fasenudisodupafam.pdfIn PDF document text
    • http://boki.hu/editor_up/xotobukur.pdfIn PDF document text
    • http://eraldocomo.it/userfiles/files/boxokexesonunubugusiduv.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/c8je8pvhenp7odfljqkb8v3tr5/wobanaton.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/54699285948.pdfIn PDF document text
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/16108a1e8766fe---69115680753.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es//ckfinder/userfiles/files/femilalaf.pdfIn PDF document text
    • https://chmelo.hu/sites/default/files/file/bikipewujiwesifijo.pdfIn PDF document text
    • https://telewebmarketing.com/FCKeditor/file/75010111131.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/86087111618.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/tuberojejuboditizeba.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/1d572f774ba55a053c894c52a214c8af/46842128841.pdfIn PDF document text
    • https://aquatim.ro/uploads/files/12890699049.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/34237f876de30af155c31381e21ecb3b/16656076092.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=physics+notes+class+12+pdf+downloadPDF 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_off0000d669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD669 17528 bytes
SHA-256: d094ac8758a4ab0fc14486b518f1c8389d9163f6eec803dd40c4d86227015c46
font_01_sfnt_off00010399.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10399 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB0 10992 bytes
SHA-256: 3dacdb62158cc6499f875bd6083dc1d748016f00c173c0f2c4c590d9f8cf8f60