Malicious PDF — malware analysis report

Static analysis result for SHA-256 b896388c91d4ffce…

MALICIOUS

PDF

80.3 KB Created: 2021-09-19 21:16:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dfb8a26981b1049606b5d80b8332399f SHA-1: 56f408442462ffea9c1be41a46dd7be9d9f3fe44 SHA-256: b896388c91d4ffce1a8492dc7166d51741c127eb8ce74a0761ab0d590717b2ca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's used for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://crysiq.ru/uplcv?utm_term=theoretical+physics+books+pdf PDF link annotation
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1613398ee76df1---wamovet.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/11717220605.pdfIn PDF document text
    • http://markfarolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/3664292354.pdfIn PDF document text
    • http://teraval.cz/res/file/23202345579.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/pekosifevigun.pdfIn PDF document text
    • http://ashole.hu/UserFiles/File/94738041129.pdfIn PDF document text
    • https://agros.net/uploads/file/89764880150.pdfIn PDF document text
    • http://davidhammerstein.org/ckfinder/userfiles/files/91992373619.pdfIn PDF document text
    • http://wawa757.com/uploads/files/memuzogexatorekowifub.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/6768956646.pdfIn PDF document text
    • https://12shio1.com/contents/files/24311386806.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/79818550343.pdfIn PDF document text
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161419827512bf---disopelirite.pdfIn PDF document text
    • https://qatarsecurityservices.com/public_html/userfiles/file/budigogasakatag.pdfIn PDF document text
    • https://www.dooleysnaturalgas.com/ckfinder/userfiles/files/91012692831.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16137b97c2cda3---93866965244.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614735a7e3091---jimezoleliremivu.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/dogovarawivadapamaniti.pdfIn PDF document text
    • http://cudicio.it/images/file/fajamusibagofupiminuxos.pdfIn PDF document text
    • https://www.tahitotfaluovodak.hu/ckfinder/userfiles/files/zeguredenewubeduxiratitag.pdfIn PDF document text
    • http://canxetaianhduc.com/images/file/dafederidowanojemazu.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/sukodirufib.pdfIn PDF document text
    • http://www.moyekolodin.com/files/44738087290.pdfIn PDF document text
    • http://teleinwestor.com/userfiles/file/nexevolotomurolineleju.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/f6735ad2affc1414bc053c22aaca245d/zazeronepuzex.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/tutinovegizixogu.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_off0000d757.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD757 16668 bytes
SHA-256: 2f90f89d19e070d6d8cfee867594592216ae17af2daba366ad47e0a91cd982be
font_01_sfnt_off00010298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10298 10920 bytes
SHA-256: 7fdf1d1295e6d9a2853612457504db6fc6535bf731c341df340932c7a457bb66
font_02_sfnt_off00011bd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BD8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1