Malicious PDF — malware analysis report

Static analysis result for SHA-256 a31a811d4647c74e…

MALICIOUS

PDF

79.3 KB Created: 2021-03-31 02:48:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 4c18638f8088facb130a032158d8a6b1 SHA-1: 773bb677fbd8dd2515a848c0b9fa364cbaebbd20 SHA-256: a31a811d4647c74efab29f8cf0f0c32830f747fb1bd14bc690662eb74806e20a
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 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://fokemale.ru/wix?keyword=real+money+generator+for+gta+5+online PDF link annotation
    • https://daxodewime.weebly.com/uploads/1/3/1/3/131398188/relazebu.pdfIn PDF document text
    • http://xoxosedefoxadu.mygamesonline.org/65238376946.pdfIn PDF document text
    • http://zemesod.getenjoyment.net/86311118160.pdfIn PDF document text
    • http://fezelegafefuv.mywebcommunity.org/english_language_placement_test_with_answers.pdfIn PDF document text
    • http://xanusojuruxu.sportsontheweb.net/36545131065.pdfIn PDF document text
    • https://xujikipige.weebly.com/uploads/1/3/1/3/131379844/2177937.pdfIn PDF document text
    • https://tuzutetenufiro.weebly.com/uploads/1/3/4/7/134716615/moginamasewivu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://mesobuze.epizy.com/accounting_standards_icai.pdfIn PDF document text
    • http://geralumumavol.rf.gd/contrato_de_arrendamiento_terreno_agricola_ecuador.pdfIn PDF document text
    • http://suvumudupese.epizy.com/gewako.pdfIn PDF document text
    • https://37e0f79d-b0c1-4727-b76d-5b759c81288f.filesusr.com/ugd/9c66ff_2114912575f54d1ebb94e55e99ad2f11.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc725a0d-78ef-4750-b89e-c72a2c0f0b1e/2005_6.0_powerstroke_hp_and_torque.pdfIn PDF document text
    • https://3ff4c494-4984-418a-b709-7a5c611cca0a.filesusr.com/ugd/adbee0_0ba229bc7010414b9cc9295d77743dae.pdf?index=trueIn PDF document text
    • http://tofezaniv.rf.gd/astro_navigation_software_free.pdfIn PDF document text
    • https://8eccd3b7-fb20-4588-a5b5-4d8c58591879.filesusr.com/ugd/0e6328_9bfb2ce9361f426c91691cc93aac4e87.pdf?index=trueIn PDF document text
    • http://wuxosalilujaza.atwebpages.com/tinolelo.pdfIn PDF document text
    • https://4cf2acc4-d143-4013-a78d-f21de0873c4f.filesusr.com/ugd/e4636f_c9575602444f44408307e43c4ddd77c5.pdf?index=trueIn PDF document text
    • https://460eb545-5389-4aa9-9e78-d1074a8bca0c.filesusr.com/ugd/21a131_7c8ad35582f447a184e874f459a74856.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/229e7bdf-1b00-4087-8097-77d56a7f28c1/majapexaruzon.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2d8c54b-af19-4cc1-9b67-32d8c143ecf0/sigmund_freud_psychoanalysis_quotes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb1bb56d-c322-4a19-8fde-5d2f83f70c42/9986842362.pdfIn PDF document text
    • http://jogulele.epizy.com/what_is_the_cidr_value_for_the_new_subnet_mask.pdfIn PDF document text
    • https://8860adff-7f0b-4cf3-a358-cdd560dff136.filesusr.com/ugd/625844_93ea3a2e35bf4a938f93cef911780d9c.pdf?index=trueIn PDF document text
    • https://6a9ecc2b-05c3-4056-8705-773ae6be8cdd.filesusr.com/ugd/7a359d_50ef4215777a4c1897d4da2f156b9441.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF79C 5144 bytes
SHA-256: b8b8fc86a5083509d789bc6130a0920e6ed1113ef34aa837ff54a98d7398d105
font_01_sfnt_off00010920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10920 11324 bytes
SHA-256: 1ef6c7c65f96ade19df48bc0f21b9165d2a6908e13ecfa357794340a4d0f7cd9