Malicious PDF — malware analysis report

Static analysis result for SHA-256 3888362e1dcf4fe7…

MALICIOUS

PDF

73.0 KB Created: 2021-07-31 06:43:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: acd2dab7c649768bf8678862c57712ec SHA-1: 8dd0f35fa523e6d70edc90aad0ce4156660791f4 SHA-256: 3888362e1dcf4fe7988d1a50f88b69a360d5a696cfda21fed2da1605932dc731
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and does not provide clear textual content, but the heuristic firings and numerous URLs are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076f8cdc4e69---1117229469.pdf In PDF document text
    • http://weifong.tw/fckimages/file/lekikijifitut.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b36772ef4c6---ranokipolozasepewafenef.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7a638d160---rovogikilodojifotepokisak.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a696c596af8---92057999736.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a2feab432---41643758862.pdfIn PDF document text
    • https://vannordenvastgoed.nl/userfiles/file/boleposodoporokirojonure.pdfIn PDF document text
    • http://progettarecasa.com/userfiles/files/sugerasumojuk.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/bc77b44f8fdb9f95b2554fd69bc693e1/51827269978.pdfIn PDF document text
    • http://www.nowsingapore.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1606f00cdb918b---raxakukokewupugimisituni.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160918c4ed8ee5---motojagede.pdfIn PDF document text
    • http://homeopathyhongkong.org/files/fafekivijozuxadam.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a5e2d75084b---60063272389.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d90ee37a65---67364666699.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/9d130e7e366d5dbff38177dc8123fbb3/xuposajolisuniwifukir.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca1ddef82a---60580740599.pdfIn PDF document text
    • https://makeswebsites.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/47901709430.pdfIn PDF document text
    • https://dongcohonda.com/userfiles/file/85637115603.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/optrtuamr1l54k26o279upm557/wubosiliwijezupezoximef.pdfIn PDF document text
    • https://rsebolivia.org/userfiles/file/domekazulimozek.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/20986334372.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/99220816327.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/0d90884f8a6ba1f7b3ee656c6e8641e7/nebadoxud.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc5b65fd7e---naxogudakumado.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=understanding+the+purpose+and+power+of+woman+by+myles+munroe+pdfPDF 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_off0000bc5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC5A 11392 bytes
SHA-256: f0ed9f531c51d7f91921d5fc64ebadf059beae46290574206702fa54772fab3f
font_01_sfnt_off0000d6a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eeba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBA 14636 bytes
SHA-256: d19953a5637094c9c6934128665ec724e0ee0ec8eaaffc9487b335f3376461ee