Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f7ec4a80c853fb5…

MALICIOUS

PDF

116.2 KB Created: 2021-09-06 17:09:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9901acdbc196d9b51d6cbc244bb93ee4 SHA-1: 6d4b644be7c146052c49497d0d153f58d53c0843 SHA-256: 8f7ec4a80c853fb55f7a8e30338e873c57b1c8ae6852daf956cabeb0ff522fac
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to malicious sites. The embedded URLs, while numerous, do not appear to be directly executable but serve as the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/d8d1aa0f3a92011d1a77f17ff0d6a8c7/febiregogezan.pdf In PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/70123242318.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/duporogutidutatibudav.pdfIn PDF document text
    • http://medica-brno.com/files/gunewajalubuwanas.pdfIn PDF document text
    • http://enewind.com/pliki/file/80772958840.pdfIn PDF document text
    • http://pensionpoint.cz/userfiles/files/budegu.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/pojusulipuz.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/2eef20eddb675831e4b50b5604e3fcb3/vewapi.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/8nqfb4ja6n98q97ihqqsjekjf3/movevofiv.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c568cf06b7a---wedexixawebopiberokipiv.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160949bde24fa4---gogosudewofusi.pdfIn PDF document text
    • http://codienlanhminhquang.com/upload/files/gufibumuribizij.pdfIn PDF document text
    • https://pointvirgule.ca/upload/editor/file/bemebubezalotujunozige.pdfIn PDF document text
    • http://stavebnevyrobky.sk/www/upload/files/62077359472.pdfIn PDF document text
    • http://hondaototanan.com/upload/files/82381896442.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c25ab6248a0---18923513702.pdfIn PDF document text
    • http://sun-tes.ru/files/file/vupakimibuvijezifovopota.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/fe927a36ff57598d5d271b6b9cbb965c/tuxino.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/novixebadazenupujulajexi.pdfIn PDF document text
    • http://tprcindia.com/ckeditor/ckfinder/userfiles/files/8886787686.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccbd887052---26043699950.pdfIn PDF document text
    • http://richmore.kr/uploadfile/fckeditor/file/pitipalogemenerugo.pdfIn PDF document text
    • http://coss-wynn-reunion.com/clients/d/db/dbe3622004495b304d8703879a486b7d/File/6177605121.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/gudixazek.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/42119f3dd3ad38a80f7739676bdfdf14/6989455899.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=delmar+maternal+infant+nursing+care+plans+pdf+freePDF 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_off00015b42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B42 10944 bytes
SHA-256: 7f911410836f77db3c111e6e733f9b669ef5bad68060a4116ee80dd19436a492
font_01_sfnt_off00017460.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17460 20512 bytes
SHA-256: a906643105a68aed81376dbcf83049ec65c3106fcb69254b02a8efb1ea9d592f
font_02_sfnt_off0001aa18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AA18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1