Malicious PDF — malware analysis report

Static analysis result for SHA-256 98e5143c2b1fdcb3…

MALICIOUS

PDF

75.0 KB Created: 2021-09-06 18:58:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cc548597937f39a89aa83464a25363a7 SHA-1: 0dd89dcb71f498de1af38661adbcc86f399a224f SHA-256: 98e5143c2b1fdcb33c6d299e3563cac4993e0f0a158a64603c12e04fd88336e4
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan threat. It contains numerous links, many pointing to compromised CMS uploads and disposable domains, suggesting a link farm designed to redirect users to potentially harmful content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing text but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://zhjpharm.com/upload/files/labubaripusuwix.pdf In PDF document text
    • http://thuephotocopytaihanoi.com/upload/files/favedamaxifaxubolulo.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/84438080107.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a43fc07e12a---87848803716.pdfIn PDF document text
    • http://slippersymposium.com/clients/875641/File/85965732726.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a150de6d86e---24383948680.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/46823554296.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/e3ff9b7f23558c423039e49d6b3c3fac/24772168422.pdfIn PDF document text
    • https://rmp-familienanzeigen.de/cms/files/negezifof.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160b2da34e7510---sejinabuzejonalogukidupaf.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b73dd60324c---wozutipaterikamisoraxu.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/6910729540.pdfIn PDF document text
    • http://xn--b1akwe.xn--p1ai/userfiles/file/89268346534.pdfIn PDF document text
    • http://dreesmann-foto.de/userfiles/file/51061900369.pdfIn PDF document text
    • http://www.syrahresources.com.au/application/third_party/ckfinder/userfiles/files/74524880006.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/ubn2dngvc0n4ve9rsqf49vg03d/jitijegi.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/rmbsc6uueebrg1b4utirh27ges/60887042324.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f068788ed18---72677074449.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1608dc3cfade61---98885271460.pdfIn PDF document text
    • https://thepainter.asia/upload/files/99333975883.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/6e3dd34ac1b86b39a9729816a4594e96/92776764972.pdfIn PDF document text
    • https://daleel.global/wp-content/plugins/super-forms/uploads/php/files/s85jq78p7ls9e4b55o1pbdt837/84921671147.pdfIn PDF document text
    • https://ngaa.org.au/application/third_party/ckfinder/userfiles/files/jesimukaxefavenarigutut.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/bofoban.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/26356337903.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=sears+lawn+tractor+owners+manualPDF 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://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_off0000c26b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC26B 16564 bytes
SHA-256: 8b4d35c7c9a53511e4b2be61ae8bd068b387815e938b67963a2a3bbeb91530c7
font_01_sfnt_off0000ed68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001057f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1057F 10560 bytes
SHA-256: fbae7a68cda3d4dfb8145b1af49882209ef5fa4e03f4cfb265b7c5dd00940aae