Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b3ebe7c3a136988…

MALICIOUS

PDF

78.4 KB Created: 2021-08-05 07:34:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 26df8aa62bba7518e788324f2c49caeb SHA-1: 379b5f30bcdafa852a223b12abb35667d616c0a8 SHA-256: 8b3ebe7c3a13698856f284debeb51a29148a6692ba9b120cb1da642a50dd8169
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution via these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ba53abbf3---45494308871.pdf In PDF document text
    • https://unique-u.biz/images/uploads/file/pijuwitidimawinubefax.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/68b8b658c3b97bc221c7958d270133bf/funelisokudajemib.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607db48f858b7---vetuxegikafuwozaredazu.pdfIn PDF document text
    • http://intproplaw.com/admin/uploads/file/18547667724.pdfIn PDF document text
    • http://sgpeo.pl/users//file/8979289923.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d21cb6105f5---buzavogavu.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099fc1fd9822---75803949388.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c2eb0e61680---worusuzowu.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/6875911179.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1a0b21adc5---biduxirupug.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/p6iastjus2g1m49fa0bfaajt67/dobopiruwamapuradinatedo.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090dab8b2068---migerabif.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160797a1d35d02---40576890528.pdfIn PDF document text
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075425b85d81---2719933996.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/598b2e8a577d421e55350e8df664f7f6/26427552123.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080dd53043ba---80198862472.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/gukegaxogu.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/ocdrd6fc9t6igt6k31pah9gho9/71958253231.pdfIn PDF document text
    • https://ancoraeducacion.com/images/gozesoma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+use+salter+omelette+makerPDF 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_off0000d100.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD100 10344 bytes
SHA-256: f9ba0bbb9af8218ab02df2d307fea88d5ac13896f548822839ff7d03c2caa835
font_01_sfnt_off0000e87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE87A 16496 bytes
SHA-256: dddfb80337fc9d8aa8c356b4efff890266566e321be11ad795db150a19af4e3a
font_02_sfnt_off0001133d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1133D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1