Malicious PDF — malware analysis report

Static analysis result for SHA-256 1356b305cfea33e6…

MALICIOUS

PDF

87.7 KB Created: 2021-09-06 14:21:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c275ad7ea1e77bffcca991b116a8ebd SHA-1: dee8ed92a419c6917a8886fbacff9ea9b351014d SHA-256: 1356b305cfea33e686ef8a81360a7265f3c6de21493e9cbd6e392d5467a5966e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised WordPress sites. These links are structured as a link farm, suggesting an attempt to distribute malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160766df0d6476---26298526410.pdf
    • http://anhopphat.com/uploads/files/teminoniberikodav.pdf
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/aadbc55bb8523cef6e8361c207680c12/mexalifapanidube.pdf
    • http://stroisvias.ru/userfiles/file/lugavosagibitosidimo.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/091840c65bfa3bd7a0968c81970657a5/nevipavikumipivegomaxe.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160b8882e88335---febazedosisutuligaxa.pdf
    • http://pivotal-technologies.com/userfiles/file/19444510697.pdf
    • http://yjsyrj.com/userfiles/file/81519573675.pdf
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/pk1093soe0c74i2k661pq66f52/pokenitixofisonatomo.pdf
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c37c802411---10052200205.pdf
    • http://evergladesharvesting.com/ckfinder/userfiles/files/75784563314.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7518673b35---tokenixinolozixug.pdf
    • http://onnetsolution.in/userfiles/file/debexujunopuku.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8ffc83511f---3516594007.pdf
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b274d23afc---fogoli.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/0h0jnajcviaaq9imb8gg731kn6/xasibigotiranurafejov.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16086eeff079c7---rituz.pdf
    • http://4grd.com/cmsimages/file/77163232434.pdf
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/34a62e195f4be544e09cf8625a793793/77912482784.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bea4069fdd5---digijilelosedolowup.pdf
    • https://noble-program.site/js/ckfinder/userfiles/files/zazijomomojo.pdf
    • http://xn--80aab8aioy.xn--p1ai/userfiles/file/74291383275.pdf
    • http://finemetal-cn.com/upload/files/niximobexemedezaxadop.pdf
    • http://vector-luczak.pl/new/fck_user_files/file/49857160522.pdf
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/wodavivedadamuwebiro.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=resistor+color+code+worksheet+answers
    • 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_off0000ec7c.bin
6e3f5d5b0f6ca2e6140dbe7817e4133060108976db3ca98139f0de009d6f292a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC7C 10688 bytes
font_01_sfnt_off000104fd.bin
fe7dbc139b042743c8775251d29f7361e149e2af856437cf4c43d5f3617766e9
pdf-font-stream PDF embedded font (sfnt) at offset 0x104FD 20200 bytes
font_02_sfnt_off000138e0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138E0 16792 bytes