Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e25a11a70b2c8f9…

MALICIOUS

PDF

82.1 KB Created: 2021-06-10 20:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: f2ff228bc4d4228d597c038a7b60cea7 SHA-1: 45c4a6f82fd3faba34d5708b687530510e33c228 SHA-256: 5e25a11a70b2c8f920e2662c3c02b0dc142d7f0f320cd3334ed5b752ad37d7c1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • 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://krisoc.ru/uplcv?utm_term=word+and+formula+equations+worksheet+answers PDF link annotation
    • http://eltonltd.ru/sites/default/files/uploads/piwopivuripesaja.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/22137194219.pdfIn PDF document text
    • http://kojeneckezbozi.eu/userfiles/file/mekanifadazupifabanoji.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7f7a50760---7199851722.pdfIn PDF document text
    • http://podlahypilat.cz/admin/file/bizixo.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608e70058a672---50493478093.pdfIn PDF document text
    • https://iescolumbus.org/wp-content/plugins/super-forms/uploads/php/files/e649db7aa663cc66560687aa03cee910/wujikurovalero.pdfIn PDF document text
    • http://careerdynamic.com/clients/3/3d/3d9dba0a3645e5854abf1db7654b9c86/File/vepuveziwojopifibe.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160900aa7a5799---13705569802.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840a6c8d794---40057993764.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021050405590473499.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/c2c337b168add4c98cdfebfb8dc306c7/25708961094.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/71925898870.pdfIn PDF document text
    • http://alkanboya.com/files/file/%5C/10189746447.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad7a239cf39---setodifi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f480.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF480 5324 bytes
SHA-256: b14e763e0c079b422fe6c508ccf53c0baf41fdb6a4015b2438d0a02bc2f7ee69
font_01_sfnt_off00010682.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10682 11256 bytes
SHA-256: 3d829b60db4a14ff16428d1efc429f95de58fec9a3d297f92e5185881b9e56b4
font_02_sfnt_off00012cdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDD 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333