Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5bff27a8b8f377f…

MALICIOUS

PDF

83.8 KB Created: 2021-08-25 19:42:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 2e4a8e583789e8c5c038ed61c84d893b SHA-1: 7ab616542384f549e5c54cdff50829f58eb88186 SHA-256: c5bff27a8b8f377fec941940c28505be304788b224aadb915608b5881cfa0d7b
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is heavily obfuscated and unreadable, providing no direct content clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/6834dc76f5c84b1a677670ee724b68e1/99205535222.pdf In PDF document text
    • http://stolizstekla.ru/userfiles/file/35350691559.pdfIn PDF document text
    • http://divorcefinance.nl/uploads//file/3532733861.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce52c3dd81c---52194948860.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/846fc8face818c26a8a60b6bd5fe0ec9/22293017807.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/99479608268.pdfIn PDF document text
    • http://sattamatkapatti.com/userfiles/file/severotegurifemilimij.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16119919d5ce2d---dapesoxo.pdfIn PDF document text
    • http://hubbardfamilycircle.com/clients/62940/File/gupolapotavobumima.pdfIn PDF document text
    • http://laconchigliacasevacanze.it/userfiles/files/36934876231.pdfIn PDF document text
    • http://gourmethousemacau.com/UploadFilesfile///5155634357.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/eiskpp0dnmc3j8r9ghveaqicun/jabet.pdfIn PDF document text
    • http://lakesnwoodskerala.com/uploads/file/dinabemixo.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/nubolivifusowoj.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d0823d0a7---fudokexunomonumexe.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16083fecd8f2c9---xixoxexaxesizofiv.pdfIn PDF document text
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160740ba591db0---tezisokifumujisil.pdfIn PDF document text
    • https://mimpiindah2.com/contents//files/butanopagomiziduke.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a2322d9ba49---nafukiduw.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb963a7a246---lumapavezitela.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607618ea3e7d4---31586370766.pdfIn PDF document text
    • http://vitanova-cattery.com/upload/file/pidafomomageluzagasemago.pdfIn PDF document text
    • http://gdlianyu.com/uploadfiles/file/gotibarinovukoli.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16108cef633a52---vipelusaronenuxiwuj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=what+colors+mix+to+make+olive+greenPDF 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_off0000e1a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1A1 10928 bytes
SHA-256: d9a7b9fe481011e5bf8fe9f3097f739b8f5ad23f4d4058ffc40f3d21ef80d082
font_01_sfnt_off0000fad3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD3 16948 bytes
SHA-256: 3e3c51a5d6e1a3bbc356a99b85bf69070c913011e66fe162af49908f6b9479ae
font_02_sfnt_off0001274d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1274D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1