Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a55899cd84ef5c1…

MALICIOUS

PDF

91.3 KB Created: 2021-07-04 05:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 75b43fe08ae4353b1cfcf23a4a31907a SHA-1: 32261f6d8ab1ca698145ade0f8ada3d92c341686 SHA-256: 4a55899cd84ef5c1edcf7dd660cab6150e7eba25086f5c200afb968eb06cdb23
164 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised websites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of these links suggests the document is used to redirect users to malicious infrastructure, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/d76d6ec3a5a65b161cfe6e48bc469206/97183406089.pdf In PDF document text
    • http://kirakuramenandsushi.com/uploads/files/9194293804.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/66707962572.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c59e7d0ef81---72397165191.pdfIn PDF document text
    • http://dongkoo.com/uploads/editor/files/90818028126.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bac4ad4717e---vopunokususugifo.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16078a8cde9a9b---31993938724.pdfIn PDF document text
    • http://runningrhinelanderrabbitry.com/clients/875187/File/basakusezije.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b7a2ce989---norogaxakitabeguxa.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098229fd8ef5---31022495050.pdfIn PDF document text
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69394411947.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/50337332456.pdfIn PDF document text
    • https://sambelteri.com/contents//files/tajalowubejofozibarete.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/j4m73l2bog2lpusnrulaaeln92/boxofubafitasokazanazumex.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/natokedopirogeverexotek.pdfIn PDF document text
    • http://baliretreatcenter.com/olabali_ci/media/images/newsfiles/33777416690.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d31f08039---12606092083.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/rubiwosugunatulazedupexo.pdfIn PDF document text
    • http://epoxidice.ro/mm/file/kupojebaseselimejus.pdfIn PDF document text
    • https://hirurgija.me//files/tejor.pdfIn PDF document text
    • http://sampsonancestry.com/clients/d/d9/d9bd9208c4e45de01aa31840e3a8c66b/File/7299916.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160b95ee989ab0---93646892573.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/6hnac91bjqgog5sea7b0242q7n/65932447849.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0a981c06a6---lukevitine.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=8th+class+history+chapter+1+question+answerPDF 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_off0000ff13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF13 18132 bytes
SHA-256: e2860d443f66fcb38aa95333d61aa203ab81fd7f4183df6ee456b01fa9718b76
font_01_sfnt_off00012dc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000145de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145DE 11080 bytes
SHA-256: e3115b623f4b0e96f7d35dce5870c995fba43f2a993df92b2e22a3c8633c62ee