Malicious PDF — malware analysis report

Static analysis result for SHA-256 7661c3d61be2202c…

MALICIOUS

PDF

75.1 KB Created: 2021-06-20 15:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 94f37437fbc8a7bd8609c6acf3693ed4 SHA-1: 3977eb2572f6abf4b7c3b28bc8d0b942f381c236 SHA-256: 7661c3d61be2202cd11cd8115c33a55f51c253939bb4db566e9f29935cc36dc4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://adance0112.com/upfile/editor/file/pikerelizomodomepeje.pdf In PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7f5a989c0---bureserigeda.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091e603e64b7---lipamiwuvege.pdfIn PDF document text
    • http://bebelino.ru/userfiles/file/jimuvakekuruwepusogokuzip.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160869c65d2f38---8462045643.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/98217421697.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/7f53fb0aeef0c1956fee6928a2e57936/57287729119.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/16078bf27410a7---13454641645.pdfIn PDF document text
    • https://securitydm.com/slicice/file/88214425207.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a744fa8223d---96687576027.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/354dc50dd5f3ffa68bc9531d9ef8a564/vesavonefanopoxelupozo.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/mesipifanowabopiwiv.pdfIn PDF document text
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/85026117874.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/51ce1f81b879c9a33900fe35b18c7ce7/bigoresakilevisej.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/43846267446.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/s05pguuo7tg6vrs39jr1prrq94/12435586554.pdfIn PDF document text
    • https://eternalbliss.net/file/sumanu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=express+vpn+license+keyPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE719 4968 bytes
SHA-256: f22e58b0e522950e032d055cc30e506f08627a56408e9aec1dd81bd658d7977c
font_01_sfnt_off0000f82a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF82A 12232 bytes
SHA-256: ddfb3db2e157b80a0332d3f51437bb54ef2d673ffb4989458db1f39b4c228d23