Malicious PDF — malware analysis report

Static analysis result for SHA-256 bff7f960b45c59fb…

MALICIOUS

PDF

85.8 KB Created: 2021-09-04 13:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 7f9aad198ef1ef6853c8669d9ae2114c SHA-1: 0984c3967cb28afd80f7ce3b8ef132ea705337f7 SHA-256: bff7f960b45c59fb277b8c88940e240fb1c93bcc3b5098557ed6107b1b09079b
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to other PDF files hosted on compromised websites, likely for SEO poisoning or to distribute further malware. The presence of multiple distinct hosts and links suggests a coordinated effort to manipulate search engine results or spread malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/bea546aa516e5aca6583920169a23405/10960100796.pdf In PDF document text
    • http://forter.vn/hinhanh/file/95930466658.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d48f89a078---dafuturoduxamupu.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/lozonaloguzubukikunir.pdfIn PDF document text
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/jefavupibebas.pdfIn PDF document text
    • http://location-venise.com/italie_documents/files/kizuludelatu.pdfIn PDF document text
    • https://bushregenerators.net/userfiles/files/bumosorerefuwevod.pdfIn PDF document text
    • http://parkhigh65.com/clients/4970/File/jagagekapupobagewona.pdfIn PDF document text
    • http://optimumnieruchomosci.pl/uploads/userfiles/files/33192880898.pdfIn PDF document text
    • https://martybermanassociates.com/wp-content/plugins/super-forms/uploads/php/files/05ab7acdfdcc76a6d0b30dc046d82051/tirapikukokofutadezona.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/59577953247.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071b0d36a7da---vazuzapezofuwepipofit.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/8cf76884a2296a2481e2d077f5942707/zivujemawewarajebunewo.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b6141af36---80549437065.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/28786478403.pdfIn PDF document text
    • https://anthonygillant.com/userfiles/file/wumebijegododutexa.pdfIn PDF document text
    • https://sanmuabancongty.vn/images/content/files/nemesavova.pdfIn PDF document text
    • https://classoft.ro/userfiles/file/gimafoxovakupijez.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-6-5/20210605064759486431.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/57bc095ede0343e7fbe4c3c15f572f08/fisiropivulilanodijov.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b0f3d5194d6---rubotisirugur.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/8a107835a1a5f7025b44b3a9bbd688af/jusuwiwoxoruvazax.pdfIn PDF document text
    • http://galgalesh.com/userfiles/file/rixunirufovetow.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/texix.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ae11da2b827---nedimebabukakusi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=mitsubishi+fridge+freezer+user+manualPDF 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_off0000e9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CD 10972 bytes
SHA-256: a970b19b779b0bd356b5164cd120d675b6ddbc34e588e66d6c992962da5aa149
font_01_sfnt_off000102de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102DE 18124 bytes
SHA-256: 9eac769f51c413b169f13029b22dbfe4236e5fbc69560e88ea3342d2d64438a3
font_02_sfnt_off000131f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1