Malicious PDF — malware analysis report

Static analysis result for SHA-256 521e7767d20d4ff9…

MALICIOUS

PDF

102.1 KB Created: 2021-06-24 09:30:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a14fa0b0817537a15efac3680ed114f4 SHA-1: 514e8c23ede1ed35eeb37b8f9cdebd4db2efc6bb SHA-256: 521e7767d20d4ff99ca3ccb7887b62eddd87860e115600b0bae3f670436a125c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as a phishing trojan. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://wastran.ru/uplcv?utm_term=barron%2527s+1100+words+list
    • https://eventaipei.com/upload/files/69641585722.pdf
    • https://cualuoihoanmy.com/uploads/userfiles/file/4606398667.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a9844b701a---goteweg.pdf
    • http://noithattamphuong.com/upload/files/93625637032.pdf
    • http://kahounova.cz/userfiles/file/texosugo.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/badaaa8aa45ed2a023febd6badc62715/49754753570.pdf
    • http://salukool.ee/upload/userfiles/file/nalajakoz.pdf
    • http://dichvugiayphep.biz/upload/ck/files/44180249380.pdf
    • https://anukulagrotech.com/userfiles/file/zigobigu.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f5faba3ab---43160610336.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/falohbbjo9m8bff6l2cgbir96h/45101343311.pdf
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/ijsi4u44cqmnr9rrb3jojkosj1/93879663087.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609deb16e478d---17999349857.pdf
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/29c134df04abbd1e2f8db35c6cfa114b/46111059846.pdf
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/24223203006.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/ogg1nua6e4a6j9c6vgsl19iod4/gagosewasetokibutonofef.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a3400c80692---32832332811.pdf
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608f111dcb772---porajagusumatijuzavu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001272f.bin
f6ca44e4d5941fc8c67077c6ed4d1993118883b3366b462519cbd5beecf794c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1272F 5108 bytes
font_01_sfnt_off000138f5.bin
3327458347e6ac447236aca74c3dd979443fe5ffeb4fc5df6e3a562ee3fb8050
pdf-font-stream PDF embedded font (sfnt) at offset 0x138F5 5188 bytes
font_02_sfnt_off00014ac1.bin
2e15b526ee7e48578f7b3864fe349517891ebc0c2ed9549be908e845180a5603
pdf-font-stream PDF embedded font (sfnt) at offset 0x14AC1 12768 bytes
font_03_sfnt_off0001752c.bin
68de6d6b34629de777ab3ab8a9f134c855f305daa617ab346a3ffef9837f5fc7
pdf-font-stream PDF embedded font (sfnt) at offset 0x1752C 16264 bytes