Malicious PDF — malware analysis report

Static analysis result for SHA-256 8373400d4a8ab7a3…

MALICIOUS

PDF

74.5 KB Created: 2021-04-02 18:50:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 3d6731c3804ea6ff7e6d171dd507ec0d SHA-1: 10d398e81e3c90df399a19e689282d9b7ad9c589 SHA-256: 8373400d4a8ab7a3947f7ac42c1b0b490dc9bec2ac9fd54e7bcc26cae4f671a3
186 Risk Score

Malware Insights

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

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. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jottigo.ru/award?keyword=precious+memories+lyrics+and+chords+pdf PDF link annotation
    • http://chebsvet.ru/printable_south_america_map20niw.pdfIn PDF document text
    • https://xizidalubatud.weebly.com/uploads/1/3/4/5/134583516/xelija.pdfIn PDF document text
    • http://devicesprotectionforusers.site/jisufereryf0vq.pdfIn PDF document text
    • https://vodazifuja.weebly.com/uploads/1/3/4/2/134265633/tinugelexi.pdfIn PDF document text
    • https://febewizonobuwom.weebly.com/uploads/1/3/4/3/134311996/pekawesumelex-duvelafimotulud-dokowim-xagotatitof.pdfIn PDF document text
    • https://lotatodekimin.weebly.com/uploads/1/3/4/7/134705716/kurarapi_tevuzezutakupod_gowolaxaj_gixom.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
    • https://s3.amazonaws.com/rirusozo/43843954851.pdfIn PDF document text
    • https://4bf641bf-117a-4913-931f-55e49063997f.filesusr.com/ugd/5befcb_403ed4f477e94b699bf3cac0d99251a2.pdf?index=trueIn PDF document text
    • https://05e27880-d5e1-4d3d-8428-ba943e9300bc.filesusr.com/ugd/b56239_0b6db65ff0e944a5af47559f44a1d99a.pdf?index=trueIn PDF document text
    • https://329f26c8-0235-4118-8622-173d264d9cf1.filesusr.com/ugd/221f3a_7a65faee72804b8a878e6acde90f9e94.pdf?index=trueIn PDF document text
    • https://9ffa65b4-b95e-481c-977d-2cf6acaa57d7.filesusr.com/ugd/f68d46_5e44dd6cb41044aa980e171e6f4cd1fe.pdf?index=trueIn PDF document text
    • https://369206df-e466-4f8f-9771-850d1edb33c5.filesusr.com/ugd/8fd5dc_577f9ff6924e44f5a9e9af38cd886b33.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mokuwanibof/el_evangelio_de_cagliostro_gratis.pdfIn PDF document text
    • https://dce09894-55e7-49e1-9c43-b94069c58f23.filesusr.com/ugd/11ae40_f8b9ee0314a747d093f7fc333b998296.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/42431b5d-2f85-4eda-af04-0284255516e8/is_being_very_emotional_a_sign_of_labor.pdfIn PDF document text
    • https://s3.amazonaws.com/vebisop/identity_verification_form_post_office.pdfIn PDF document text
    • https://94cb5446-44f7-499c-8ddd-8d9df3a2db3d.filesusr.com/ugd/9b9c26_84054a42d3b449ccb8213212d7d57205.pdf?index=trueIn PDF document text
    • https://b24182fa-1fee-416c-9f57-41d8a36573e1.filesusr.com/ugd/1cc367_983af6d4b57f47ef8e079c932d6377aa.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gafedupeba/new_movies_bollywood_online.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/72feb0d3-d220-4112-96fd-2ae8f3a0d5ae/fojelebiguguxevetoximowa.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD945 5300 bytes
SHA-256: 6b40d5366234685ddffbccd5ddad6790896748034aeae0e3f4d3127dbb7f3bad
font_01_sfnt_off0000eb10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB10 10176 bytes
SHA-256: a1a540b501d10042d757521c347e25335f44028bd9079bc8b9ed644412f76083
font_02_sfnt_off00010df8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF8 4324 bytes
SHA-256: 1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361