Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b58ecbbbe9b9c28…

MALICIOUS

PDF

84.4 KB Created: 2021-06-30 20:42:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c917e74908360827c1c55aa810bb6973 SHA-1: 78f579368071307c9929335c9de4d1a8bad53f30 SHA-256: 6b58ecbbbe9b9c28300554f31dfe3ffe10d7e863e3bdb35dd41e8908cd7f99a1
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and links to compromised CMS upload storage suggests the document is designed to exploit vulnerabilities or trick users into downloading further malicious content. The heuristic 'SE_DOWNLOAD_BUTTON' further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c95d0217c41---49767773081.pdf In PDF document text
    • https://voyagerf.ru/wp-content/plugins/super-forms/uploads/php/files/c89235055db20cedaf982c8e79ba641e/wefujarelefitokosapikapob.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b72067b879e---22168830108.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/sg90uupel4npgi3dvpvjh3tb5h/9615069926.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/160da935e4fc70---88479448018.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f33f1d96c---kiguwokoma.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5203a8220d---tuwerexu.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/bae2d3816b8b1346748c64f43e55e642/73078605754.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a28ca3001---tadenidezirufakinirusazuz.pdfIn PDF document text
    • http://arserwood.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210503023245705302k8lcg0.pdfIn PDF document text
    • https://medicinasolidale.org/wp-content/plugins/super-forms/uploads/php/files/dc1d5a56a8c1a19b2a1af7b43be9a194/81065566389.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc3a446139---42911256825.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d46f87ae1---lozomon.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/ckhkkj8bssj153jkvctilp6qdr/kimupor.pdfIn PDF document text
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c1f00f66f---73018599128.pdfIn PDF document text
    • https://alarrabnews.com/images/content/content/file/74289211218.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/d898c6c991525e294a01b1c369bb22b2/xuroripezodogopadugavulo.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c4f8db1795---6240042070.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/dd79a0c88f0d76b880f598718a1c3cee/dapewik.pdfIn PDF document text
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/6md7obt5higkbjtb351sc3ugh5/bebexebinulojajarevoso.pdfIn PDF document text
    • https://tepihtrava.rs//files/54893482303.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606de6e83718e---budakozimorob.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160875e5213c6d---zupolodod.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071cb2dc939a---58416803745.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=pdf+to+powerpoint+online+free+unlimitedPDF 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_off0000e877.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE877 10516 bytes
SHA-256: 1965b048423307b6f0557ac9ac1692204576ee6e5b9fead8dd7fb610f54c2c0b
font_01_sfnt_off0001005e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1005E 16868 bytes
SHA-256: 81883c1869eb4b4d909cdd5f07c04557f6c16f95992c167e1a12db4c6eee0fed
font_02_sfnt_off00012bf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BF2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1