Malicious PDF — malware analysis report

Static analysis result for SHA-256 889df2122ab889f8…

MALICIOUS

PDF

74.0 KB Created: 2021-06-07 03:09:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 0873002b6b96bc03f962cf93f73c32ce SHA-1: 1cb56515c2aed2a1963ee001776028c2c6dcbe2c SHA-256: 889df2122ab889f8b3dc6264e21c00b4477200005302c0a9c3904f6298469dc5
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to websites that appear to be compromised WordPress installations, identified by heuristics as a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate maliciousness, likely for phishing or malware delivery. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, suggesting it was generated programmatically rather than being a user-facing document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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=divisores+de+12+18+9 PDF link annotation
    • https://www.truegridpaver.com/wp-content/plugins/super-forms/uploads/php/files/25216873ce94cd1a068a1e1f70add663/tufuf.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608320247ce37---ponipokefabudokusozixogir.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16077fb9ce6089---mixozajobidekogogugazutuk.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/d379a94d02cda0d2298f500dcd4ce0e8/4929911847.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/afetkmtm7ofisb7vvts5kvbae3/midogifoxexogatuv.pdfIn PDF document text
    • http://hocikto.info/userfiles/file/45023507227.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/72061838106.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/iv6efpnrrum6lddprgmoh2iul5/wujidugudoma.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/ralososemejugoxoradew.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/a8908e6b2cdeecfefdaa2b52a83560da/1872819293.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/44329575b6f6f682a6bf565625bb8529/jotepalu.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/5m98ue2kcho2ut13f5aveibjpr/kuwidovukalomazi.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/160a58ea9a5b09---rilovatigi.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//zijexine.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/c2d594aef8ff4459105ba0601557829c/46630965933.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d465.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD465 4772 bytes
SHA-256: 16870d214a923250d361b809a43c06ac4820630d2ee42219e4c9350ad5fbf299
font_01_sfnt_off0000e4aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4AA 11764 bytes
SHA-256: 0e5a37b61f4d8a23fac98ca71a1d383d129ec936ffebe6f55cfd4ec18ebafa29
font_02_sfnt_off00010b2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2D 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34