Malicious PDF — malware analysis report

Static analysis result for SHA-256 f189e83b1023588c…

MALICIOUS

PDF

79.7 KB Created: 2021-09-23 10:30:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aae9a9f61555c8874fb3643517b41778 SHA-1: 3630dfbecf035c17507db64d783882018de3463a SHA-256: f189e83b1023588c64f8a323a59ec20c089d711fdcc8c3a00527828cd7bf1fc6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a ClamAV detection and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to redirect users to potentially malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://sudhirsachdevaclasses.com/ci/userfiles/files/78143932486.pdf In PDF document text
    • https://www.emcp-pmce.ca/_includes/ckfinder/userfiles/files/32880686098.pdfIn PDF document text
    • http://clinicaveterinariagussago.com/userfiles/files/wamizuralakeroxerijar.pdfIn PDF document text
    • http://wsmr.us/userfiles/file/83778267464.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5777cf152---23966859946.pdfIn PDF document text
    • http://ogcdc.org/uploads/ck_upload/files/10467589219.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/57641780901.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/m9flgnn2g56kj61pr4otg4cr69/xewoxomo.pdfIn PDF document text
    • https://asiapharma.la/files/files/9765168333.pdfIn PDF document text
    • http://wamaeassociates.com/images/uploads/originals/file/70960425126.pdfIn PDF document text
    • https://rwd1.thadv.com/upload/files/powodiseniwufinimi.pdfIn PDF document text
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jiduxesarotikek.pdfIn PDF document text
    • http://tajeer.co/userfiles/file/31692404733.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146b6527afc4---42162197458.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/jr4j9u5v2ajhbnlkqbt6ofp59s/xobuvevabitovunajijever.pdfIn PDF document text
    • http://planbmedia.hu/files/19034763392.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/55725173801.pdfIn PDF document text
    • http://ac-kenigsberg.ru/files/file/36891262908.pdfIn PDF document text
    • http://isvpro.com/custom/files/kixunuduxokodatakox.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/dewaximemoninon.pdfIn PDF document text
    • http://101eyewear.com/luutru/files/12151417996.pdfIn PDF document text
    • http://juentai.com/userfiles/files/nejowudogo.pdfIn PDF document text
    • https://somogyplusz.hu/files/91257314075.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=android+feature+phone+in+bangladeshPDF 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_off0000d380.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD380 17368 bytes
SHA-256: c67cc2d7f710cd799880e859305def5c1da06062bba1472b20fb02727c2cc295
font_01_sfnt_off0001000f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000F 10996 bytes
SHA-256: 1d7692dbb84956c9a83a0023370cf7aed4cacd1a6730f6d44996cde47686c5bd
font_02_sfnt_off00011918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11918 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1