Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9845aa7786371eb…

MALICIOUS

PDF

83.0 KB Created: 2021-09-18 14:46:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: df55e65cc8fea62db5703f77167b72cc SHA-1: 7a92ef0a9135ee116e769c1cb4d36c78f20389f3 SHA-256: c9845aa7786371eb959d698ab237fbf4a9ce28d84a7a0d9686a5457e1ca07011
224 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains embedded JavaScript and is flagged by ML classifiers as malicious. It also exhibits characteristics of a link farm, with multiple URLs pointing to potentially compromised or disposable hosting. The critical heuristic 'SE_SECRET_RECOVERY_LURE' indicates the document's intent is to trick users into revealing sensitive recovery information, such as private keys or backup codes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 8

  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://geriatriccarenewjersey.com/userfiles/files/fexobuguz.pdf
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/58432459926.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/dhbcbnm88q8g5ate8blcb7h4gg/27615328398.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fb65594776---48956120384.pdf
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcb34e48f3---niguji.pdf
    • http://woodbridgeabw.com/uploads/files/47200401712.pdf
    • https://alubiasdetolosa.com/files/galeria/files/bewox.pdf
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613361f5a468e---fisefufonifipos.pdf
    • http://gerastar.com/userfiles/file/nejewidawo.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613f64d9302ac---4457789306.pdf
    • http://klimagra.pl/images/wysiwyg_img/file/femuvixalabogi.pdf
    • http://clubesquilacoma.com/uploads/files/nusabowigikate.pdf
    • https://stillwaiting.org/userfiles/file/xorajewovaxe.pdf
    • https://amoslodge10-org.alljobsinliberia.com/ckfinder/userfiles/files/zivawuvelebabexemi.pdf
    • https://foodphotoshop.com/userfiles/files/78537366738.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a9837d243---72600147673.pdf
    • https://grnca.org/img/files/files/meputenido.pdf
    • http://skupka54.ru/upload/m/5791776175.pdf
    • http://bfcy88.com/uploads/files/sezinuxumebejaramo.pdf
    • https://legend-chang.com/UserFiles/files/bakupepalofe.pdf
    • http://brkvinc.com/userfiles/file/96934538270.pdf
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136846df080f---28121151240.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=office+2016+product+key+generator
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000db00.bin
a04aff865e9f7596bc3431e0ccd9015dfa3abe1a3525a75596f5d340faee603d
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB00 11376 bytes
font_01_sfnt_off0000f5d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D6 16792 bytes
font_02_sfnt_off00010de8.bin
c7fd93806066889654af571962661e56cac9cbf442da630f8f80696bb0f88b26
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DE8 18496 bytes