Malicious PDF — malware analysis report

Static analysis result for SHA-256 66a768064769d807…

MALICIOUS

PDF

69.3 KB Created: 2021-09-30 22:33:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 384fa95e10494840d3a5841fde8d5aec SHA-1: 397b99cf19410b52b3df8d22d20e2e7b9919b6a5 SHA-256: 66a768064769d8075101c8549bd3972ca629412f7b13246ebf8abbe9b3dfcec7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. It also features a link farm with numerous URLs pointing to various domains, some of which are identified as compromised CMS uploads. The presence of these elements, combined with the ML classifier and ClamAV detection, strongly indicates a malicious intent, likely to lure users to external sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://inwebjor.ru/uplcv?utm_term=ullu+apk+mod+unlocked+download
    • http://www.fred-robin.com/ckfinder/userfiles/files/59919795686.pdf
    • http://www.tamtrebinhminh.com/public/files/99577565422.pdf
    • http://www.americaninvest.net/upls/files/65639155153.pdf
    • http://agrion.org/upload/fichier/10971302441.pdf
    • http://videlec.be/ressource/file/zuninevuma.pdf
    • https://skl.deindrukdemo.nl/upload/files/96021323595.pdf
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/58053953438.pdf
    • https://ratsimae.ee/media/contents/file/mopamuwodoxefetixinad.pdf
    • http://jiuxingchaoshi.com/uploads/file/091436089019.pdf
    • https://samuelben-horin.com/userfiles/file/detozazalasifowomo.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1614b3671733ae---16327750754.pdf
    • http://lonerangerfanclub.com/ckfinder/userfiles/files/likawudusiwofamajem.pdf
    • http://somkuthyoptika.hu/editor_up/11930590455.pdf
    • http://marine-inox.com/i/File/99083793988.pdf
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/161509368bc6e0---75706646165.pdf
    • http://bumsnab.ru/uploads/files/pudejakabum.pdf
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/rulojivipadowur.pdf
    • http://cuspsurgeons.com/userfiles/file/wemebub.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16148b294923ce---niziji.pdf
    • http://veterky.ru/ckfinder/userfiles/files/tuwezorusibaw.pdf
    • https://profipreklady.cz/www/ckfinder/userfiles/files/visim.pdf
    • http://www.elstar.ru/uploads/files/kusovuwapawijisuv.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_off0000afaf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAFAF 16792 bytes
font_01_sfnt_off0000c7c1.bin
71ed309ef5a3181cedd4ac634b1f9fae509e62394c66f030c7f151b456bfb6b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7C1 15804 bytes
font_02_sfnt_off0000efc6.bin
f272c85ed8b7d0089a368d549c30391691e01351c105970cef7027d0473a046f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC6 10500 bytes