Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a5844e0143344c3…

MALICIOUS

PDF

80.5 KB Created: 2021-09-07 19:21:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 79a4186dbf22d117a26c63d2c57283fa SHA-1: af265a0ee6384f626ee9a75962f6074071d2b631 SHA-256: 5a5844e0143344c309b74191fa8dd293cc9e22fb7472f68f5d658e6c8e2252fc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous links pointing to potentially compromised websites, suggesting an attempt to redirect users to malicious hosts. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://sklepjola.pl/userfiles/file/bubovina.pdf
    • http://bjsprt.com/uploadfile/file///2021052620044621.pdf
    • https://wfca-czech.cz/temp/userfiles/files/75003586469.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5b641af5c---xefimuziniketimad.pdf
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16112523f1827a---54255922895.pdf
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/6ss0cu9ap16abf6n32rsj5vbdb/pewidupasakuf.pdf
    • http://droneducational.com/admin/userfiles/file/66224214488.pdf
    • https://singaporenotarypublic.com/wp-content/plugins/super-forms/uploads/php/files/72733fb02812de78ca6de003b4a7c418/somaxazixolewuduzeveli.pdf
    • http://pinzimoniofiumicino.eu/userfiles/files/nedokibekafanakofiti.pdf
    • http://meskerjager.nl/media/files/lobenikaxuzutuluduw.pdf
    • https://dolupin.com/calisma2/files/uploads/varemuw.pdf
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/16026949366.pdf
    • http://d4svancouver.com/clients/c/c8/c8601140a4283eb9b700f388a83987a3/File/49945737861.pdf
    • http://vetcasatenovo.it/userfiles/files/woxajetulejoxafi.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/7b8bet3g5gh1np35kg7t56tp98/42163223118.pdf
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d07b37442b6---vadatefutaxixodu.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077180ce4849---7974573944.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/7d58e8b888f4ed7d5e4f2dee143eea59/66992335965.pdf
    • http://www.recko.ru/ckfinder/userfiles/files/gosiwajegitemon.pdf
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/kq06p8eo8ma1qkbal0hn01rndm/lexaludupoxesupoxud.pdf
    • http://alnadaoil.com/userfiles/file/fokajagetit.pdf
    • http://scuderia512.com/js/upload/files/66812511361.pdf
    • http://torby.kbo.pl/ckfinder/userfiles/files/98170250939.pdf
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/bizejedogudonemede.pdf
    • http://zabbeleecooking.com/ckfinder/userfiles/files/50655026299.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/rout40ku6lh85lj4ti8ho5lnei/79462884970.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=partituras+de+canciones+cristianas+para+piano+en+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_off0000d136.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD136 16792 bytes
font_01_sfnt_off0000e948.bin
eb02438a7224976af92322865ba091315254ba28648c2bb050e266564c45070f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE948 19860 bytes
font_02_sfnt_off00011b53.bin
0bb97ac63d2cd59413e18295483a4b301bc4c369de4ad652cea049d567117c32
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B53 10668 bytes