Malicious PDF — malware analysis report

Static analysis result for SHA-256 9594215bfb5abb3d…

MALICIOUS

PDF

86.8 KB Created: 2021-09-02 13:58:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6630523cbbcf5e88324940e2ee004544 SHA-1: b682ddf6c70eaad1e69c3dcc97b00be9d27f0d9a SHA-256: 9594215bfb5abb3d48285973cf542a01ac8055b49c606379ab8b146e40bd88cb
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and by an ML classifier. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to lure users to malicious destinations. The document body is heavily obfuscated and contains no readable content, further indicating a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840d9c71622---14899371514.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/5mvghkrs4h6ht3ouf72tjn7f04/xeluxugux.pdf
    • https://www.libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/6710595719.pdf
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/pmemrrug3t758jl2lle0ns9oqh/rerudasipamosuzotutu.pdf
    • http://ud2-140.com/files/dalapofuvubizazorafoval.pdf
    • http://mtegl.wsystem.sk/userfiles/files/getopilibozugujewuzuvubuz.pdf
    • https://sgdivorcelawyers.com/wp-content/plugins/super-forms/uploads/php/files/67b81ba95d929e0f80976fcb2f5a3fac/7302125852.pdf
    • http://grandp.ru/userfiles/file/kukomuxasenozib.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/1cf5a8d3d453fc2f37d76cc5df7d7703/23975685088.pdf
    • https://amursvoidom.ru/media/files/85768465875.pdf
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/5b5a29d34534b18463766e823a6fa490/38845401171.pdf
    • http://chukysovin.com/img-svc/files/xivimigezisitofid.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/faf1980ef0cabd1de524dd5f80dd8257/javagem.pdf
    • https://eastmanllc.net/ckfinder/userfiles/files/xerenisowedozekilu.pdf
    • https://begili.com/uploads/image/files/59885288387.pdf
    • http://hieuchuan.com/upload/files/67223148245.pdf
    • http://www.carolglassman.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f94399601a---muzusorelu.pdf
    • http://cs-golfclub.com/ckupload/files/33869189308.pdf
    • http://ziconiavip.com/uploadfck/file/4199268036.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099dbc930ae0---xeduxavazusixod.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/c440cf037b68390d164db95369513d04/wetoxivebegavizuvif.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ab6bb013ab8---golevase.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/711316544b062738a92cbb2e71ebbb4f/14059081990.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160d1f3bbbb775---73239596151.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=sistema+de+costeo+por+ordenes+de+produccion+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_off0000eb3b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3B 16792 bytes
font_01_sfnt_off00010352.bin
96b8203bed2c281671edb31fe1279e329510e29a6f8afd0bf654f60de13cd8de
pdf-font-stream PDF embedded font (sfnt) at offset 0x10352 10908 bytes
font_02_sfnt_off00011c89.bin
53efd7572c7fd179afda90c05419162c44fd078db3b3c4df2d23a7ad84b84262
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C89 19040 bytes