Malicious PDF — malware analysis report

Static analysis result for SHA-256 d594938a95a73ae9…

MALICIOUS

PDF

73.9 KB Created: 2021-09-24 22:54:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f4d5baa8dc8954ca326c9ff5fe3d0acb SHA-1: f6c1c6f2f668b9c12ea6200d9b76ec6b2e81afdc SHA-256: d594938a95a73ae9b56b36938356bb02eb94a212605fe2faab0dd85fd9fd8765
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting. These links form a link farm, suggesting an attempt to distribute further malicious content or phish for information. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

Heuristics 7

  • 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 https://pistant.ru/uplcv?utm_term=drastic+ds+emulator+apk+patched+no+root
    • https://costarica4d.com/contents/files/62013952320.pdf
    • https://buonoantonio.it/userfiles/file/97597778688.pdf
    • http://ain.proximeo.com/ckfinder/userfiles/files/milubal.pdf
    • https://atputasbaze.lv/images/userfiles/files/85256858721.pdf
    • http://healthywithhart.com/res/file/12557028451.pdf
    • https://www.sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/ruredavan.pdf
    • http://nceed.kr/pds/userfiles/files/fekisukijebukiwokiwomexi.pdf
    • https://secolink.sk/userfiles/file/55372704222.pdf
    • http://vakaruinzinerija.lt/userfiles/file/firuze.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137c1e47fd27---42952073551.pdf
    • https://equantumconsulting.com/files/files/1968763137.pdf
    • https://petek.biz/resimler/files/bareruxivelaz.pdf
    • https://tdfstore.it/file/witapimupomiragirures.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e394fb0935---47521453716.pdf
    • https://benhgout.net/uploads/Files/file/75720530414.pdf
    • https://tekdalyapi.com/upload/ckfinder/files/12087519916.pdf
    • http://tilestone-pools.com/i/File/65721947628.pdf
    • http://seoaudytor.pl/userfiles/file/64950942864.pdf
    • https://kozhikodedeaf.org/admin/my_files/file/verumejufeb.pdf
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/161422a8305590---vovugugowirawurirabo.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-9-11/20210911184708654653.pdf
    • http://jujucuisine.com/userfiles/file/40722750995.pdf
    • http://michelschuurmans.nl/images/uploads/file/78114123676.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614dbe1cb656a---reziwa.pdf
    • https://ski-valloire.com/ckfinder/userfiles/files/ludipiduperilinula.pdf
    • http://weforyou.it/userfiles/files/38569334202.pdf
    • 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_off0000b788.bin
352d2676e7acdf06aa33a3014a3e18c19c2773a720b41c4ca18eb1eec11e72f6
pdf-font-stream PDF embedded font (sfnt) at offset 0xB788 10972 bytes
font_01_sfnt_off0000d0cc.bin
d739ccdb6d181b7f670ad9b17ea15f3255f149a6872347afa3d5ac2bd2224edc
pdf-font-stream PDF embedded font (sfnt) at offset 0xD0CC 18084 bytes
font_02_sfnt_off0000ff2e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF2E 16792 bytes