Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0e05c9cc59ddb7b…

MALICIOUS

PDF

76.5 KB Created: 2021-09-18 10:04:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b54d1a4ac90dd03bd5104c17f3598dc8 SHA-1: 6910708b8f347f757961a87f082a393aefe05399 SHA-256: a0e05c9cc59ddb7b71fb141067fd541b6b6548f6ca0c4ea290999c00c230c665
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF format itself can embed JavaScript, which could be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://huntic.ru/uplcv?utm_term=spider+man+stickman+rope+hero PDF link annotation
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/a31765dab7d2a073c84e85eef1fef8df/71814234667.pdfIn PDF document text
    • http://humansharehouse.com/userData/board/file/jojudijalij.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/98088463013.pdfIn PDF document text
    • http://poliinc.com/upload/files/96354381363.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/27609786552.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/rutub.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/68032305492.pdfIn PDF document text
    • https://kaptenhoki.info/contents/files/kikepuropurimifuwew.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/0tu4rolis7snf5s85f0qtoobit/19704719065.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/38131273075.pdfIn PDF document text
    • https://apra.pl/files/file/60715942309.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144f2f8e49f4---60905409676.pdfIn PDF document text
    • https://koratspring.com/upload/file/dolorekow.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/mamexudazew.pdfIn PDF document text
    • https://dadrarad.ro/userfiles/file/dizujupif.pdfIn PDF document text
    • http://ed-web.cz/userfilesfile/74136961426.pdfIn PDF document text
    • http://makassitools.com/userfiles/file///91369969205.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/75735880552.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/932283639.pdfIn PDF document text
    • http://navigator-nsk.ru/userfiles/file/piwob.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109031852025485.pdfIn PDF document text
    • https://bahispesinde.com/gnc/veri/_files/ruzekowa.pdfIn PDF document text
    • https://alrashed-alsaleh.com/userfiles/files/kadiku.pdfIn PDF document text
    • http://prplus4u.com/ckupload/files/dolefikoredapaberemuzif.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_off0000c259.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC259 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA70 10900 bytes
SHA-256: 460ca7ff98b9be0a0880461954ad30a5516fbebdd2221279b350c913cf54bf14
font_02_sfnt_off0000f36e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36E 18544 bytes
SHA-256: f7e969c4f484611ab1641c405f46a2f975d12649880f82af37bad4e30aacf343