Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa8dbce25a26e5b5…

MALICIOUS

PDF

76.2 KB Created: 2021-09-05 05:46:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a9f321f87f9ec916c960cf7cabb628c SHA-1: 6030b755ed4bf56db6d6fb1902697c47fa903ec4 SHA-256: aa8dbce25a26e5b5668786a101f7734292198cf6819be316a583df88efa17305
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and ML classifiers, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The presence of multiple external URIs, including links to compromised CMS uploads and link farms on disposable hosting, strongly suggests a phishing or malware distribution scheme. The embedded JavaScript likely facilitates the redirection or download of a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 7

  • 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.
  • 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://sirinthepgroup.com/userfiles/file/fetele.pdf
    • http://cravaluos.com/ckfinder/userfiles/files/668261068.pdf
    • http://agendaalzheimer.org/files/galeria/files/91964901088.pdf
    • http://greenbiotech.vn/uploads/userfiles/file/muwotobusekamuvupimobebog.pdf
    • http://elturo.ru/img/upload/files/wupanetajedid.pdf
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1610814ef513ac---bexevewenizadulonidamamag.pdf
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d8243ab0d---29373489819.pdf
    • http://jarosi.hu/files/file/20159170033.pdf
    • http://driver-jazda.pl/upload/file/6814977215.pdf
    • https://novamakine.com/upload/ckfinder/files/fudelulotakubofanasalewo.pdf
    • http://tragiaocolamsapa.com/userfiles/image/file/karukipewetaxosivelaso.pdf
    • https://wildarium.com/ckfinder/userfiles/files/45906779050.pdf
    • https://vipbeachhouse.com/uploads/editor/file/pasubikasekuxitubej.pdf
    • https://giustofiori.it/file/sajakezuneja.pdf
    • http://docando.es/js/ckfinder/userfiles/files/74950724454.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b3b48297a0e---72769020290.pdf
    • http://omeofest.eu/userfiles/files/nozogerokibijojejoxuko.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/aa576ec6da12b6e033044c6219a67b89/69505780202.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c96263e06dc---63128481317.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f866e8402c---8030592846.pdf
    • http://www.fred-robin.com/ckfinder/userfiles/files/zowok.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=class+9+maths+ncert+solutions+chapter+6+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_off0000b952.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB952 16792 bytes
font_01_sfnt_off0000d164.bin
68107c7d042291fccff75c90e4bcafb10f7400b94fd8438ccfc0d1c1d1e54f62
pdf-font-stream PDF embedded font (sfnt) at offset 0xD164 21204 bytes
font_02_sfnt_off000108ed.bin
f2ca346e9603be5f20e30c017765be8ce127afa7a2043679831f236bd615c8da
pdf-font-stream PDF embedded font (sfnt) at offset 0x108ED 11352 bytes