Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f678e6158f8b886…

MALICIOUS

PDF

75.0 KB Created: 2021-09-24 13:47:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bc2b30cd990e2071da36290daad8f2da SHA-1: 86c82b92dab60b016a96959db620b8797d0a99c6 SHA-256: 4f678e6158f8b8866fcf2b72e8ef28bf6bcf6b837ce8ac77aed4a665f9440ebb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting. This suggests the document is designed as a link farm to redirect users to malicious or phishing content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://veterinariacomportamentale.it/userfiles/files/luninefa.pdf
    • https://tigapilar.com/upload/files/44091680171.pdf
    • http://zjgyuanhong.com/v15/Upload/file/2021952215166264.pdf
    • http://ylphs.com/ckfinder/userfiles/files/33141461211.pdf
    • http://chipublichouse.com/ckfinder/userfiles/files/55899022562.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613ec5c26e6e0---30920374060.pdf
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/ec6377fc3f88f12e6a112e323aefceb5/23515776520.pdf
    • https://newcar-rental.com/uploads/files/202109150221171045.pdf
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/6287509435.pdf
    • https://rent-1.es/ckfinder/userfiles/files/zikaxokusuwudaxun.pdf
    • https://memorybg.net/app/templates/js/ckfinder/userfiles/files/35685610182.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/98c30b95695710cad8d4b3a32ad551f7/97486381409.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161359113acba1---matomivupaguka.pdf
    • https://consurs.ro/ckfinder/userfiles/files/fofilimonot.pdf
    • http://youandisagenix.com/ckfinder/userfiles/files/45297873915.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140d8f1164c2---35202956892.pdf
    • https://coebmsf.com/userfiles/file/rokevaledim.pdf
    • http://akkoryazilim.com/userfiles/file/giwutibotibibev.pdf
    • http://www.gieskestukadoors.nl/ckfinder/files/files/96454160414.pdf
    • https://nk-sostanj.si/files/file/93431833096.pdf
    • http://sun-eko.eu/files/file/65772849967.pdf
    • http://baheth24aqari.com/ckfinder/userfiles/files/liniverine.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161495ea854221---50586565341.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=a+textbook+of+fluid+mechanics+and+hydraulic+machines
    • 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_off0000b9aa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9AA 16792 bytes
font_01_sfnt_off0000d1c1.bin
6332c921ae65081708fde11c07285e50ae16866b7bbf0a11a7fb2e0c255d4798
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C1 11272 bytes
font_02_sfnt_off0000ec09.bin
bccee365eb3313ee1fc94fb0191e0227c81bcea4eba322ae9badbde2a9738e93
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC09 19064 bytes