Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c7d577b9b4b9ee8…

MALICIOUS

PDF

79.5 KB Created: 2021-09-01 23:25:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: d2bb8683dd2481afb2738b2d50f23d02 SHA-1: eb81e5c9b41a81c86fbdbb996e5a576607aa1409 SHA-256: 5c7d577b9b4b9ee85cbaf1c5b0223f812202864007c0a2337d8676aceec83ba2
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to potentially compromised or disposable hosting. Heuristics indicate a link farm on disposable hosting and compromised CMS upload storage, suggesting a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://khiconghoixuancong.com/Khicong/admin/userfiles/file/48160095908.pdf In PDF document text
    • http://hoacanh.net/luutru/files/37504174893.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/pokivas.pdfIn PDF document text
    • http://vkp.ru/upload/global/file/geduritiwulenunuzuxuv.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/migidolibinipa.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160af67d118062---rupepoxebegavirububibibu.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/nubibigem.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/xulazivux.pdfIn PDF document text
    • https://audit-advisers.com/userfiles/file/44078430144.pdfIn PDF document text
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/bavenakesimesupoviz.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/nq08r2b480t5nnf0ev3elnj6a0/42977234704.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/zimibewimogosobozixerop.pdfIn PDF document text
    • https://pasarantogel.com/contents/files/72751891171.pdfIn PDF document text
    • http://pereplanirovkaoblast.ru/pict/file/58287329000.pdfIn PDF document text
    • https://nieruchomosciturystyczne.eu/files/file/lutajerefadipuxi.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/99049640192.pdfIn PDF document text
    • https://silky.ae/images/bulk_images/files/zabirisavoruvopabifite.pdfIn PDF document text
    • http://haniltm.kr/upfiles/editor/files/28434327939.pdfIn PDF document text
    • http://28777886.com/Lpf/UPFILE/userfiles/files/wepilipopimonijov.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160901ded0ed0d---14156543643.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/bajepinenolajitowel.pdfIn PDF document text
    • http://www.mecateengenharia.com.br/ckfinder/userfiles/files/53025786216.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=r+words+that+mean+strongPDF 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_off0000d370.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD370 10688 bytes
SHA-256: 603e7bb75e08f996bd5f8937c2aeea400fc3e0eca51074e8ed068fd7022d0197
font_01_sfnt_off0000ebaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C1 17188 bytes
SHA-256: 9223400bdb2f7566a17f2ebd80f07910984ebd7c7cc6bb086c0f39ff62c94f26