Malicious PDF — malware analysis report

Static analysis result for SHA-256 6c63471dfea8fe66…

MALICIOUS

PDF

77.6 KB Created: 2021-09-20 12:51:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d94bc2414fe98dab5cf34e8a62d5adae SHA-1: a1ed2a6e42ada23ca3805cf97f6d41014f09ed01 SHA-256: 6c63471dfea8fe66fb3304d3ea4237842cb90071cf944f9b0320785743864add
156 Risk Score

Malware Insights

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

The PDF contains a link farm, with many URLs pointing to external sites, some hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9855

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://phoiinnhiet.com/images/uploads/files/51681240756.pdf In PDF document text
    • http://beautybybelief.com/admin/images/file/99202777554.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/dekotoloziravulibuzad.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///jonaberabamurubazetukegag.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/27813863007.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/gamixi.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/tovarivu.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/ziwikatubixelawoki.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/582306f4a3612d54dca1ac850c3347b9/rutirafiwiwurobalojase.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16140c7a9b7a04---zukagudarugidutezalik.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/33842790083.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/sexunijeso.pdfIn PDF document text
    • http://kapalishakti.com/ckfinder/userfiles/files/42557712120.pdfIn PDF document text
    • http://rakkhunnursinghome.com/user_img/files/63212343297.pdfIn PDF document text
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/42172247991.pdfIn PDF document text
    • http://nesthomes.in/userfiles/file/7755694033.pdfIn PDF document text
    • http://lyzebrno.cz/userfiles/file/10720610460.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/vuvuxuzuludiratixobagiluj.pdfIn PDF document text
    • http://sarica.com.tr/ckfinder/userfiles/files/fokosedopawalatapim.pdfIn PDF document text
    • http://yunnanyingxiang.com/ckfinder/userfiles/files/14100120340.pdfIn PDF document text
    • https://allegypttours.net/userfiles/files/tisuz.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/dinulirabumikovojonikixag.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/47889715765.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1613088f6c9243---zudugoxir.pdfIn PDF document text
    • https://olboihorgaszto.hu/editor_up2/ferifuxeziwefulaju.pdfIn PDF document text
    • http://vendsol.com/userfiles/file/nutaxujaliwojuzo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=super+mario+bros+ds+emulatorPDF 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://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_off0000ce78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE78 10764 bytes
SHA-256: a608f892edabd3811ae132459bb5eb828c0e5444b701d51b134214f14de98479
font_01_sfnt_off0000e6f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F7 16772 bytes
SHA-256: 832c741b7ee798578c77396c1f65f5531446df0577d40afa9f7f466a93e7a456
font_02_sfnt_off000111fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111FD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1