Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1c2a8f8d2fc4d6a…

MALICIOUS

PDF

78.8 KB Created: 2021-09-20 17:37:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f2c596b6daa92ff3e889b767929dc253 SHA-1: 52cf8f1d437e602f9ede741ab19be715f78a65bd SHA-256: f1c2a8f8d2fc4d6a28bdb35a8c214ff625a89672d44846b8ae49daf5b5273822
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with many embedded URLs pointing to compromised WordPress upload storage and other disposable hosting. These links likely lead to phishing or malware distribution sites, aligning with a spearphishing attachment attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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.
  • 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://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f8f639c9ae---50540954795.pdf In PDF document text
    • http://chernogolovka.inhome360.ru/admin/ckfinder/userfiles/files/riwekad.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109051823347974.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/96336209748.pdfIn PDF document text
    • https://hgb.se/filer/file/97792108737.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/nobetewiparane.pdfIn PDF document text
    • http://www.ctnphrae.com/ckfinder/userfiles/files/nelixojidugekodesepudi.pdfIn PDF document text
    • http://studiogallerani.it/userfiles/files/nazobonaxinenuzefemajenoz.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021091911253973499.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/63224006502.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/vgvpskm5vvbea7ev80tp2vq6ka/92408984513.pdfIn PDF document text
    • http://3suntech.com/UploadFile/file/20210914145646888.pdfIn PDF document text
    • https://tonere.shop/app/webroot/files/userfiles/files/28010050032.pdfIn PDF document text
    • http://mtt-association.fr/upload/file/5146347964.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d325c4fae2---fovexavipasilo.pdfIn PDF document text
    • http://quiltingacademy.info/fckeditor/userfiles/file/xuvexezodutozubopusum.pdfIn PDF document text
    • http://coolbiotech.com/upload/files/robosimebaravotasu.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/91204939282.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/48988748022.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/girukisid.pdfIn PDF document text
    • http://recrute.fr/files/files/kiguxedaworivi.pdfIn PDF document text
    • https://qwert5.com/psum/admin/userfiles/file/44297870468.pdfIn PDF document text
    • http://majstrissmt.eu/www-data/file/ripivef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+hide+galleryPDF link annotation
    • 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_off0000d0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8E0 17444 bytes
SHA-256: 07dbca6b4923dcaf595ad874a91907013bba296fe7099df1c417894d012aa674
font_02_sfnt_off00011649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11649 10444 bytes
SHA-256: 9889e64e75141f90772fd44cf19a419a37593cf5c2e0224a55c844593085b2b0