Malicious PDF — malware analysis report

Static analysis result for SHA-256 75c106c1b717b70e…

MALICIOUS

PDF

91.3 KB Created: 2021-07-28 12:28:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e64bb6f7f5ee74c478a9eae3d5027df3 SHA-1: 4bcc9407a42a6affed95f28d53215f5cb0a25f5e SHA-256: 75c106c1b717b70e8e0cb39e5c465264c88f8564d0fae59fb503e17f0e3dcb7d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking readable content but containing embedded URLs.

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://veno2.com/upload/59649696264.pdf In PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160e13d6683ccf---wakapuzebeba.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/e4ec4164e8f3ebcf44ccf11e505fda44/mupikemaxo.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a0f422a86d3---20089640290.pdfIn PDF document text
    • http://www.esthemed.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608662d2372a4---kilipezis.pdfIn PDF document text
    • https://aedwea.com/upload/foto/63217311087.pdfIn PDF document text
    • http://zovsh.com/Uploadfiles/files/98991953329.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/6812815051.pdfIn PDF document text
    • http://tnetimes.kr/upload/file///romaned.pdfIn PDF document text
    • https://edubox.mn/uploads/users/0/files/kutogopikapivexed.pdfIn PDF document text
    • http://zangerlelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/68908389353.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/fb1190dea91fed6d9519986abcb9d672/95518528251.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160fa22eb395c9---20260003419.pdfIn PDF document text
    • https://investkwik.com/userfiles/file/kewumopuwozoj.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/7c2bba59281a3e20254e04e709cdd7f3/zemosasalese.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/mogomezorogowusubakudufu.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16074b3764bdd0---ranovirijufudefulose.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/e262742b66213cb54e88159b3b6aa798/22383062800.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/luvuwa.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160a34eff5b7b4---78098801808.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/lenugifuditakejovasifov.pdfIn PDF document text
    • https://rajaunited.com/contents//files/34564635880.pdfIn PDF document text
    • http://wrhs1967.org/clients/6/61/617565fc8afb9cc6d18abf932d248b7a/File/94003806042.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/jrs4i540ggjacit16b0k7nnrm2/revud.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b3dde09608f---vamuziw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=las+venas+abiertas+de+am%C3%A9rica+latina+resumen+capitulo+1+yahooPDF 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_off0000faed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000112ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112FF 18340 bytes
SHA-256: 3a4bc346a8351e067635f43f0ee505053a0a6575c4c9a46acb6f3d062576e9c0
font_02_sfnt_off000141b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141B5 11360 bytes
SHA-256: facf6db776d9aea35765ddf60e1d259645b839eec0a42d4737d45d4cb9027c74