Malicious PDF — malware analysis report

Static analysis result for SHA-256 51425d60091087de…

MALICIOUS

PDF

84.5 KB Created: 2021-03-15 10:43:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: c9ab82b1db212eee1b33f4fb5ebdf066 SHA-1: 3aebdfd5c1525f304dce9de3432c0f01b96a2a15 SHA-256: 51425d60091087de0d64239a407a4f1ced4849e5ffbd495bae71d33131115226
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection (Pdf.Phishing.Trojan) and an ML classifier indicating maliciousness. It contains a significant number of external links, many pointing to disposable hosting, suggesting a link farm or phishing attempt. The primary malicious URL identified is https://druttle.ru/strik?utm_term=el+coronel+no+tiene+quien+le+escriba+english.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://druttle.ru/strik?utm_term=el+coronel+no+tiene+quien+le+escriba+english PDF link annotation
    • https://bepagiji.weebly.com/uploads/1/3/4/3/134352373/51712.pdfIn PDF document text
    • https://winugemu.weebly.com/uploads/1/3/1/0/131070294/29d109e3f1bf.pdfIn PDF document text
    • https://gakewejodum.weebly.com/uploads/1/3/4/9/134902465/fifetosomerogub_lavawogelobef.pdfIn PDF document text
    • https://cdn.sqhk.co/wifavizen/q4nigii/skateboard_3d_hacked.pdfIn PDF document text
    • https://cdn.sqhk.co/jusulikipe/hiSibhc/pemonorifi.pdfIn PDF document text
    • https://rugepokowefi.weebly.com/uploads/1/3/5/2/135294276/4dc80d502.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d89d6b52-6e76-4e18-bccb-bd7428cfddad.filesusr.com/ugd/02beb7_89cd4465a87c4fb0bb3b9bc97ad29d7b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9d74f73-a313-479a-b08e-d41cbd657655/28300570867.pdfIn PDF document text
    • https://4cd5a77a-be8d-44ba-8952-4177873115c4.filesusr.com/ugd/930050_6285411fa6494e8f85fe0421650a54e9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/919c559a-4f46-42bf-8608-639959f49603/green_smoothie_recipe_spinach_banana_almond_milk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f1698980-bf8f-4b0a-bf42-b2bc68ad2abc/supexoxemepunokovuxa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4be8b1a-ca28-4e40-af5e-2c88e2ed843b/mafupufevefiw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fb4026c2-814c-4285-99a6-435d501f5181/how_do_i_write_an_essay_about_my_goals.pdfIn PDF document text
    • https://cf176ec6-4820-456b-adf9-61e5f06c968f.filesusr.com/ugd/43d598_3eede81c545d4861b5c058bad074598f.pdf?index=trueIn PDF document text
    • https://0b7b936c-93ac-4a60-9644-6ba220b934cc.filesusr.com/ugd/b4bf80_c2f6c3811e6646ab967109286d79e072.pdf?index=trueIn PDF document text
    • https://da89e6ec-52f9-4c28-8de8-447a2e923c0c.filesusr.com/ugd/5e5b2a_50be5da1c34b4ec2bf3cc00b0fe56fae.pdf?index=trueIn PDF document text
    • https://66f9544f-8325-470d-a543-c07714603334.filesusr.com/ugd/4b2642_db4f3f2597e84271b9de81db6d584ce8.pdf?index=trueIn PDF document text
    • https://12350a4d-732a-4148-85a7-4fa27f2a77ec.filesusr.com/ugd/17beed_81a1ea3b321a4fdeb2948f20dfba6f64.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_off0000ffbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBE 5284 bytes
SHA-256: 587b6894727941500cd9dd88c50ab0b2166678b8c72b3b8ddcda187b488d0e42
font_01_sfnt_off000111b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111B1 15620 bytes
SHA-256: 22fde52642052676dac143af0a3feb75142adf738fc474d708227e7337174290