Malicious PDF — malware analysis report

Static analysis result for SHA-256 872b6506d4e13a92…

MALICIOUS

PDF

84.6 KB Created: 2021-09-01 11:32:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e8ee6364aa617d62886e92a9fcbdbe2e SHA-1: ed8a0c287f3192a362b1d30126303c5d199e234e SHA-256: 872b6506d4e13a92e742699088e9f38acc4800ced4477c8b69ab25974b9faea9
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites, suggesting it functions as a link farm. The presence of these links, particularly those hosted on potentially compromised infrastructure, points towards an attempt to direct users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6282

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 http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b333eaf659---80143452097.pdf In PDF document text
    • http://osayit.com/images/file/59241868865.pdfIn PDF document text
    • http://desertofohio.net/clients/4/43/43f38f6e2239b09326489e1ba67fa1b6/File/41248976210.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/72ae40715b7a320b6579e4c9df2f685a/gamatumaxevolelukusulun.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/74068400946.pdfIn PDF document text
    • http://colafranceschi.it/userfiles/files/jinavav.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/dolaxefaxova.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1609826aa9eefa---67064995210.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089589e79f09---jixupuladabi.pdfIn PDF document text
    • https://tigercabinetry.com/wp-content/plugins/super-forms/uploads/php/files/fa4900c824324d08d9693f6a8158650b/vakujiratefejixu.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/zifiwijijerazuril.pdfIn PDF document text
    • https://la-klamm.org/userfiles/file/25492171206.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087d3e2b421f---fememarodabejulobogumopen.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/32587777389.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1609e6e7362cc6---12506018446.pdfIn PDF document text
    • http://rezidencianestor.sk/app/webroot/files/ckeditor/files/xukumadevi.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d7734c176eb---letajenomuritabifamine.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/ckrshrp2tm6q5sc9fkp8khb1p0/44986897679.pdfIn PDF document text
    • http://clickvay.com/upload/files/mubadevu.pdfIn PDF document text
    • http://calliopegoodrich.com/clients/73417/File/dizogap.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/zejifidiliserofowodevogid.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=fifty+shades+of+gray+parents+guidePDF link annotation
    • 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_off0000ec8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 18148 bytes
SHA-256: f881a763b6b405ac41b69705cc93c7974b9c026bbe244cfd04ca20113e02a44b
font_01_sfnt_off00011bc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000133d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133D8 10924 bytes
SHA-256: fcc3dd6903d60c4cee8a4076c2bf06c316e54398e66dd596c898c874dc1bb639