Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a4801d0d38ee824…

MALICIOUS

PDF

78.6 KB Created: 2021-09-10 02:18:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 0073c4a64ebf0d5b80e53d5990ffdd91 SHA-1: 9281ef521d165b9fbec9a6acf3e591bc9e7cc3f6 SHA-256: 0a4801d0d38ee824b55dde5994e70843d068fbb7eb513d57c86e944dbce90f86
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the nature of the links and the PDF structure align with common phishing and malware distribution techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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 http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffb36841fa---dejaw.pdf In PDF document text
    • http://duet-czluchow.pl/userfiles/file/77355110513.pdfIn PDF document text
    • http://ros-audit.com/i/up/file/jomuxobesi.pdfIn PDF document text
    • http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/76329662147.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210902_065111.pdfIn PDF document text
    • https://ehotelgateway.com/bot/ckfinder/uf/files/lubabovunekuxipemasupom.pdfIn PDF document text
    • http://aj-freight.com/ckfinder/userfiles/files/menokipomulevikodifevete.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/biderufebewu.pdfIn PDF document text
    • http://radissonhoteltraining.com/userfiles/file/14532657955.pdfIn PDF document text
    • https://035620126.tw/upload/greenkitchen/files/bedinalib.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16134f98f8b95d---visisowigigaz.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/br5rbe05odb0om3ph42umbuf2p/dudibemoniz.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/77622330608.pdfIn PDF document text
    • http://noavarservice.com/ckfinder/userfiles/files/gokevipobovozediku.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a18a58b702---zirizun.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/10709258023.pdfIn PDF document text
    • https://volnynaklad.cz/data/file/39631517914.pdfIn PDF document text
    • http://vencedor.coop/images/admin/file/karanegakurofoji.pdfIn PDF document text
    • http://hexindechem.com/upload/files/59367436552.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/tozekigizepogamuxu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=vertical+bar+latexPDF 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_off0000cc90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC90 19216 bytes
SHA-256: 58a85e789dd34cd8db88ed31e0ade91cb16fbd918c3a5bad105b5cda80c66fae
font_01_sfnt_off0000fedf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEDF 10044 bytes
SHA-256: a81d4a2a0fa988c2f9b81f8c1f407769edd75fe714859d9b80cb91b3c1ab13dc
font_02_sfnt_off0001155b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1155B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1