Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f0e5ca5f4c927c0…

MALICIOUS

PDF

76.0 KB Created: 2021-09-06 01:08:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f62e569be658f812cc01dfc6668f4563 SHA-1: 942c7e97edae8092e6b59763af1eb56f510540e8 SHA-256: 3f0e5ca5f4c927c0893f022701f21ca016c881be57310e588df5bc6c1f6d2d48
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document that contains numerous links, many of which point to compromised websites or disposable hosting, suggesting a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect the user to malicious content, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://fred-robin.com/ckfinder/userfiles/files/43137473508.pdf
    • http://redigonda.it/userfiles/files/23075970.pdf
    • http://self119.net/upload/userfiles/2021/08/files/210808162631.pdf
    • http://splogservice.ru/content/file/punopenetawolaferidugeb.pdf
    • http://c2ctrading.org/cms_upload/files/27278814387.pdf
    • http://nwatchonline.org/userfiles/file/72300962565.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806f5978daa---49719445259.pdf
    • http://mindentudor.hu/userfiles/file/58877625106.pdf
    • https://pcparts.fr/ckfinder/userfiles/files/lukubatud.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c87b674f457---90740339100.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080c77e5d2bd---5161349730.pdf
    • https://szekszardportal.hu/userfiles/file/lavijizapufevo.pdf
    • http://lhdrum.com/User_File/UpFile/file/20210829184827_bG9qdXJ1eHVrb3h1ZGV3b2Z1eHVi.pdf
    • http://22vek-omsk.ru/fck_editor_files/files/nonamuxonadubolize.pdf
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/bf47158badae8b6bc0d06e8abf75dc9a/76425928455.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b411f228b2d---1261317298.pdf
    • https://linhquan-group.com/upload/ck/files/13220197406.pdf
    • http://phongkhamthienhoa.vn/images/files/41563881790.pdf
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/cbe02ca51640d3f38eee778c2850828a/46983035781.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ca24128808---57781234074.pdf
    • http://starkhigh1972.com/clients/d/dd/dd83d6d7846a033806cdb512e10d7d7c/File/lulujukorikawe.pdf
    • https://mymango.ru/wp-content/plugins/super-forms/uploads/php/files/cd6928a9ca2b91968c6f84ed045d8694/wutisewudevovewotidok.pdf
    • http://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16071ef957b285---vufobuz.pdf
    • http://eiak.org/upload/editor/files/34442399485.pdf
    • https://oilbasaro.com/web/images/ckfinder/files/20210903062533.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=iso+22000+lead+auditor+training+course+material+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c4c4.bin
d5edfcfc8ef19bd32f28992c22c1b7a7165289846dd711d7f690b6f2c4944faf
pdf-font-stream PDF embedded font (sfnt) at offset 0xC4C4 16408 bytes
font_01_sfnt_off0000eef4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF4 16792 bytes
font_02_sfnt_off0001070b.bin
c1590d3b2568b820f74ad98d50089a39e37a5a83af4f58131eed6e0eabf1e8cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x1070B 11256 bytes