Malicious PDF — malware analysis report

Static analysis result for SHA-256 85c25263c0f79bf7…

MALICIOUS

PDF

69.3 KB Created: 2021-09-06 04:26:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 22aa9944dd82346c9506d4888793bfdc SHA-1: 796ced173af5c8c92feeb46938ac28f31e6483de SHA-256: 85c25263c0f79bf70768a2ad907515b0077330bb256158f15beb049fda8953ce
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains numerous external links, many pointing to compromised WordPress sites, suggesting it functions as a link farm. The ML classifier strongly indicates maliciousness, and the presence of embedded URLs points towards an attempt to redirect users to potentially harmful content. No scripts were extracted, but the overall structure and URL distribution are indicative of a phishing or malicious redirection campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • 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://ketchas.ru/uplcv?utm_term=coordinate+plane+printable+worksheets PDF link annotation
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6e53b23bc---18424272533.pdfIn PDF document text
    • http://kapli74.ru/upload_picture/39536470545.pdfIn PDF document text
    • http://mrhobbscoffee.com/images/uploads/file/silaxiwawiwog.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/82320519994.pdfIn PDF document text
    • https://samsunyapi.com/userfiles/files/deragug.pdfIn PDF document text
    • https://sunsoftinfoway.net/ckfinder/userfiles/files/70371846272.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/9935d977bf10da5ac2c52d0de0bb50a4/nenimerajetisaviwamuk.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160f8c44eb0826---lifuzepu.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a53e9f2b8c1---56671450256.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609826c900682---mekawepegokipifozufusonaj.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/kodakunub.pdfIn PDF document text
    • https://lawweb.info/mycms/admin/userfiles/file/baxifokemulewagezipejur.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba69cfbf51f---77280803202.pdfIn PDF document text
    • http://schokobrunnen.com/idata/dewofenebirirasidanewu.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ed3b01275f3---zalelujesinefenogatif.pdfIn PDF document text
    • http://lycee-elm.org/userfiles/file/2374736193.pdfIn PDF document text
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/16075c13c72956---46101371041.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080f98f614d8---ruzekevaxugafivegifefupe.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/5obesp5mqocrssv2ovtt4l896r/butotunujibesupijebuma.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/a956ee4e3578ad031876322f05abb7a9/47523383402.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021071304451681.pdfIn PDF document text
    • https://svltv.in/userfiles/files/gifefazinitorikevotevenu.pdfIn PDF document text
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/giwutogu.pdfIn PDF document text
    • http://lyjclinic.com/ckupload/files/50435024108.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_off0000b2d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2D2 14544 bytes
SHA-256: 48959660da1f19594d86c7b74c27caeda95107156becce1dafcd53ff885d9123
font_01_sfnt_off0000d6ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF04 10840 bytes
SHA-256: 645d7f1db0544a0da016b2b2792f5ca6e09908ae598325d78d9184dc5f05b63e