Malicious PDF — malware analysis report

Static analysis result for SHA-256 a37133b854141273…

MALICIOUS

PDF

83.9 KB Created: 2021-06-07 18:17:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 72dc818307b0013a1d8cb8b3bef66ea0 SHA-1: 7187b7eb3a6cd8104f5c25503ccf9c5be4febfa6 SHA-256: a37133b854141273b7cb19a172fa0787795ca927480dc05b51194b762e6069db
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 0.9996

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://huntic.ru/pbw?utm_term=calculadora+de+ecuaciones+diferenciales+homogeneas+symbolab PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4365546/normal_603e9be9a0994.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4483082/normal_601aef118c663.pdfIn PDF document text
    • https://wufodiwefoveve.weebly.com/uploads/1/3/4/8/134891768/mesoraxonunedi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464522/normal_5fcfa02e791ff.pdfIn PDF document text
    • https://nasovakuj.weebly.com/uploads/1/3/2/3/132303133/jebijivigu.pdfIn PDF document text
    • https://sulidisige.weebly.com/uploads/1/3/4/3/134318683/76592.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417813/normal_5ffa57c2338d3.pdfIn PDF document text
    • https://gumevuwogixuxuj.weebly.com/uploads/1/3/5/3/135317748/9211428.pdfIn PDF document text
    • https://wisufomerimugil.weebly.com/uploads/1/3/4/0/134016782/zenubifewi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443812/normal_605f42d13a66c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404285/normal_606228bb815f6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4529095/normal_60296febdf2eb.pdfIn PDF document text
    • https://guduzuzej.weebly.com/uploads/1/3/1/6/131606672/7264598.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://ruwezebom.pbworks.com/w/file/fetch/144425055/desafio_del_amor_para_padres.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f57586f4-10a8-45cd-a870-30c6ac57c7ea/pokemon_go_spoofer_android_download_apk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d0b90ec-3f02-4ee5-9696-8b44b0d52128/2008_jeep_wrangler_unlimited_x_accessories.pdfIn PDF document text
    • http://nilanom.pbworks.com/w/file/fetch/144416232/61307679533.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cebea00a-396f-42d0-a5f3-028698b0f44a/how_many_calories_in_a_small_caramel_iced_coffee_from_dunkin.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E7 5504 bytes
SHA-256: 6726b18d029e1f49e89504793ea20ee08ed2257a36682c21b8385e3a2facb685
font_01_sfnt_off0000e862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE862 1908 bytes
SHA-256: 8ab923703a6cb8420f8fca7bd3ad5728ba4bd58dd88d5cf9a7680080d3c28edf
font_02_sfnt_off0000f1b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B2 12620 bytes
SHA-256: 583717d753a3e8cdd3543ef18ac75034b140fcbd0e3f109ab7b0c4b5a41b0e9e
font_03_sfnt_off00011b6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B6F 16284 bytes
SHA-256: e6f1f354978e3f94c015014fe2ec2d5e9b58a2d1d612fa4055b48792e3d2fe93
font_04_sfnt_off00013109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13109 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333