Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fd5d8cc9adc2907…

MALICIOUS

PDF

76.7 KB Created: 2021-08-03 08:14:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8f1944b0c76148aa27ddb12feab735d7 SHA-1: 24f2331533a7b14e3ad58c255fe86ef2edf7245f SHA-256: 3fd5d8cc9adc2907770a732313e13efdb3e404cef804e0a581afe82528068643
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous external URIs and link farm patterns, indicating a likely phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were extracted, the presence of compromised CMS upload links and disposable hosting suggests the document is designed to redirect users to malicious sites, potentially for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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://crewmak.ru/uplcv?utm_term=classworks+student+login+desoto+county+ms PDF link annotation
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098e4ef33004---monisagiduxima.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f333998838---bogifoganowipigoxebuz.pdfIn PDF document text
    • http://taiwan-casters.com/userfiles/file/wividuxuworodapoliwa.pdfIn PDF document text
    • http://mhfmjournal.com/data/22/2/55/64/2544879/user/2788947/htdocs/userfiles/file/65991647821.pdfIn PDF document text
    • http://fsnmmaterials.com/UPFILE/userfiles/files/60982572894.pdfIn PDF document text
    • http://aep-tc.com/cache/fck_files/file/jidaxel.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/2dqvsg7asc3ads1v07i4t41np8/vulojeri.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/42321029897.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609164a9e7699---80011924728.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/vijanupiwawaf.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/buzogegafumoviredosudir.pdfIn PDF document text
    • http://hanasushipickup.com/uploads/files/rijalogodenomesipoju.pdfIn PDF document text
    • https://rumahbaruku.com/contents//files/bikugubosadidomidujog.pdfIn PDF document text
    • http://bienbao.org/uploads/files/dilejofes.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160829772dd2e9---boziwowezafuxesufin.pdfIn PDF document text
    • http://hf1968.com/clients/48820/File/xudawefijenada.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/hv1qc3ak5u1pti7dgug9ld494i/49026716249.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/5b30796b4c5451c3671977f0ea2c52b8/kajiwejuk.pdfIn PDF document text
    • https://equinox-e.com/upload/files/dilolukofefik.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/cf2df0209227b9a5c9e6c71ac7d6121c/37899839196.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5de553531f---12697425982.pdfIn PDF document text
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160832e0c28685---polajufeb.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a78f52b47e5---92101808085.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/84163365517.pdfIn PDF document text
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/53836485078.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_off0000c881.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC881 16460 bytes
SHA-256: e376994125eab1edbf4a96b89b6b8f92c0bf091500da98b24c367a02557c60a7
font_01_sfnt_off0000f335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF335 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4C 11136 bytes
SHA-256: 6c51881454eeaa796c5c993b5411f8824b8e74cdab007b8035b3c0d6def3b851