Malicious PDF — malware analysis report

Static analysis result for SHA-256 c57139da26ef1346…

MALICIOUS

PDF

114.3 KB Created: 2021-06-28 08:03:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 10946d10ba086d75733bb1cb028775fe SHA-1: b1132b2ade644934f019466cf1dfa44fecfab316 SHA-256: c57139da26ef1346c254a967ce2c5107e21c720e91a8006fa7869178921354f8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a phishing or trojan distribution attempt. The document contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure point towards an attempt to exploit users through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://chcial.ru/uplcv?utm_term=urticarial+allergic+skin+reaction
    • http://brownewingfamily.com/clients/a/a4/a4d7a48ed280e719b438ae57db99af5e/File/jubazinefetejan.pdf
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/94ef9onoo6sqn38t5m1662qd5f/sazinotisuwadagal.pdf
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/37d3b161f31cd94b7664d612da9663fd/83167568899.pdf
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/c3c6de78faa804f34888e2ba2410ba4d/28674004982.pdf
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/35c70f83384d0b73a5cea3dc3d93a00d/weripujuzodilad.pdf
    • http://retailcop.ca/files/jawiti.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4d3f7f8ed---79821577739.pdf
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1d92e2e64---duruga.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845a14018b7---39059268644.pdf
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607cac0fa7aad---12094784391.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/e36ba53acf02d1d86e98d47a588a035f/nalozegodumobolokuduk.pdf
    • http://chanakyaaerospacedefence.com/userfiles/file/63881057949.pdf
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/59f9947b500e16b57d5e769d51f59044/tizazorukisusamubaja.pdf
    • https://okvino.it/file/97173812152.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b6be34e7a5---mifukipovibexonuritofujuk.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_off00015d5a.bin
09bc41dba9d50d8e9a8fb5f5e189cda731edc7ed71025096946ce00b6f9db1d0
pdf-font-stream PDF embedded font (sfnt) at offset 0x15D5A 18020 bytes
font_01_sfnt_off00018c84.bin
4613e9cc2f45acdcc77bc0f0073b0acc5786671dccdae73b8a9d30e704aaad8c
pdf-font-stream PDF embedded font (sfnt) at offset 0x18C84 10504 bytes
font_02_sfnt_off0001a488.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A488 16792 bytes