Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ef5e03bed9d40cc…

MALICIOUS

PDF

73.9 KB Created: 2021-10-04 02:27:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: bdd1b30a4d11a33b3ca3fd2b27a2fe66 SHA-1: 2b52e807b0bb15356356d9bc60172fa830b6cf4f SHA-256: 8ef5e03bed9d40cce3818f9803c98d7e1045a1257456d09dc804f907117e71bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as containing a link farm pointing to compromised WordPress sites and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. While no scripts were explicitly extracted, the presence of numerous external URIs suggests an attempt to redirect the user to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://synerhu.ru/uplcv?utm_term=building+integrated+photovoltaics+ppt PDF link annotation
    • http://www.oomewatersport.nl/upload/files/tobofafimolosowutono.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/rosfte0m6vmh0da5e2rntgh7oc/lejewewesusi.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/161370657d301d---tiwoxowepawo.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16159c02995cb1---45922249209.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/pjp4ridltcalv28c5u56vjr5d6/28557733320.pdfIn PDF document text
    • http://zhjpharm.com/upload/files/xetilefaxisepaweriton.pdfIn PDF document text
    • https://wcfkenzi.com/ckfinder/userfiles/files/fagozodarikemuvawolerifo.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/zapozusulob.pdfIn PDF document text
    • http://zpb-maciejewski.pl/upload/fck/file/58448496188.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/gexipokonepimavokab.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/vimezefedifitopilexa.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/71951266741.pdfIn PDF document text
    • https://silverstonedevelopments.com/ckfinder/userfiles/files/97081607070.pdfIn PDF document text
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/gamekufel.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/vafoxovalimep.pdfIn PDF document text
    • http://budoprojekt.eu/obrazy/file/bilugupafaxuvef.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/takapimuzu.pdfIn PDF document text
    • https://kakakmanis.com/contents/files/56249846319.pdfIn PDF document text
    • https://djennebeads.com/nbloom/fckuploads/file/binal.pdfIn PDF document text
    • http://89928386.com/uploads/files/202109112305415360.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/161451d6b1d8a8---34814792316.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB65A 18428 bytes
SHA-256: f08134b659d73beb5f3e70bbdf4a41dae505ecbf43988379ef92e506bf329d41
font_01_sfnt_off0000e690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE690 11012 bytes
SHA-256: f9d23c6f8bced964e823e490cc025571507cf220f6085363553ed65c89198468
font_02_sfnt_off0000ffed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1