Malicious PDF — malware analysis report

Static analysis result for SHA-256 40169a5e4a070174…

MALICIOUS

PDF

108.8 KB Created: 2021-09-06 10:51:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 23aff955b6975953a357759b4e58a2c2 SHA-1: 70089507f68b1303fa0f8fedfdec1b3638e3b341 SHA-256: 40169a5e4a070174af8a0760e74ad0b041a1cac0c4b87d5fa8927bbee066f6be
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 are hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO poisoning to redirect users to malicious content. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://nucamsa.es/userfiles/files/xemafozerafi.pdf
    • http://mclarenquartz.in/ci/userfiles/files/kipupaxize.pdf
    • http://multi-accueil.fr/ressource/site-image/files/46368993386.pdf
    • https://by-express.com/upfiles/editor/files/xasotakaralaviduzifezalor.pdf
    • http://automsystem.com/UploadFile/file/20210623042804435.pdf
    • https://eletvital.hu/uploads/files/depejumotikir.pdf
    • http://cosmikkino.ru/sadm_files/tevezibivodubivororusosu.pdf
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b8ead043e8---5229922900.pdf
    • http://totoquynhhuong.com/upload/files/kisogodofasomoni.pdf
    • http://factory-01.com/js/upload/files/37684492659.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610ba9c3a1d3d---77164789065.pdf
    • https://digireg.ch/upload/73791137362.pdf
    • https://jokerprod.net/userfiles/file/momivedalofom.pdf
    • http://wintec-samu.hu/uploads/files/pokepunifukuroxixebuwet.pdf
    • https://luiginoiobbi.com/userfiles/file/mazofesolosipabokatijizod.pdf
    • http://thessalonikiflights.com/files/files/57125504292.pdf
    • http://jevades.com/aircraft/fckimages/file/nuzuzojepikarunimewivuz.pdf
    • https://vegan-eshop.cz/data/file/wugepozapenegoleximovasep.pdf
    • http://ahxxzx.com/userfiles/202108/file/sivenupekefesotim.pdf
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16081aaffa88f4---lixigunuja.pdf
    • http://www.peopleoftheheath.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab80c844826---zomesugabaxifek.pdf
    • http://safarekhoob.ir/basefile/safarekhoobir/files/72313218006.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=2019+honda+hr+v+manual+transmission
    • 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_off000136f6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x136F6 16792 bytes
font_01_sfnt_off00014f08.bin
f2e810120c7e930adc27eed330c38b747c0d152652eccfe737d6102058e3e193
pdf-font-stream PDF embedded font (sfnt) at offset 0x14F08 23236 bytes
font_02_sfnt_off00018c7e.bin
d698f203eec6984be6e69a38cd68a1b26b20d863b4e985a9ea61a8fb69a98e00
pdf-font-stream PDF embedded font (sfnt) at offset 0x18C7E 10912 bytes