Malicious PDF — malware analysis report

Static analysis result for SHA-256 a003c8b4dbbf67b1…

MALICIOUS

PDF

82.8 KB Created: 2021-06-16 10:03:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 183c3c592328eb3a66a7423e999f8dc4 SHA-1: 45fa9bf27ee92d9e74ce45a7d42a9c4525ccab65 SHA-256: a003c8b4dbbf67b1fbd5596758cf0d172f313ab69bf19ee7626d3477216c43aa
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

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

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://allytemp.ru/uplcv?utm_term=skyrim+sex+pack PDF link annotation
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/498b1597be2cb7283dd41c9abce49680/dotepebuxuvebetewose.pdfIn PDF document text
    • https://avela.md/userfiles/file/gugipavumilagawijope.pdfIn PDF document text
    • http://kfbi.ru/content/file/45948300644.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/3ds6t16dleb29o8dip2dvmrk0g/40279235882.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/7ea6bd4d4a1c9b83e2f977c3d09c6cb6/leriwosi.pdfIn PDF document text
    • http://jagodkaprzedszkole.pl/userfiles/file/tudoduvupasefotipijiwawa.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608d86687e2a0---1933610925.pdfIn PDF document text
    • https://valve-toho.com/userfiles/file/39326272728.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/83bd166f229afdfe95d7651b129b6b32/wiwumabiwu.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160784ae0b990d---nebogezi.pdfIn PDF document text
    • http://jkmdc.com/aversystem.com/userfiles/file/vekaxuladuj.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c92b9faba02---tuvisemug.pdfIn PDF document text
    • http://herculesestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fevazowopevolomuvatizom.pdfIn PDF document text
    • https://www.spreefahrten-berlin.de/wp-content/plugins/super-forms/uploads/php/files/vef00hmo305btn1c287t9pleph/pusudugaximugalok.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/39447048105.pdfIn PDF document text
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160958b496c93d---bezajigupixepepodosik.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/zufalovuwub.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102CD 5384 bytes
SHA-256: 862df9efef7b4c44a9653ce71da61c81c7c6e90875c6cfc046df05f8873c3907
font_01_sfnt_off00011514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11514 12608 bytes
SHA-256: 19c6a3f943034a86f1968a1238954bde6f2c28d83a116e3b46d5aeed1fce2ffb