Malicious PDF — malware analysis report

Static analysis result for SHA-256 935cd9a0d75c407f…

MALICIOUS

PDF

77.1 KB Created: 2021-05-12 11:49:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 331750f13e1cab1b361c69d24ac22fc8 SHA-1: acf2b459c8a1b5b87c7ea0c5817105d1f980050a SHA-256: 935cd9a0d75c407f0600c80c9216d0803cbf3ba32319fcb4ecc56f62bc515e5d
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or phishing operation. The presence of embedded URLs and the overall structure strongly suggest it's intended to redirect users to malicious sites, likely as a phishing lure or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://resalured.ru/strik?utm_term=polaris+sand%252Fsilt+bag+black+280 PDF link annotation
    • https://ralanuda.weebly.com/uploads/1/3/0/7/130775203/xenezove_vamozutiwog.pdfIn PDF document text
    • https://safasisi.weebly.com/uploads/1/3/4/4/134472516/ludet-fejat-vovutejoxet.pdfIn PDF document text
    • https://paruleponovaro.weebly.com/uploads/1/3/5/3/135389889/5090900.pdfIn PDF document text
    • http://tryporte.xyz/54804709778cggru.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389353/normal_605166157dbab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486534/normal_602a212ac3f31.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369638/normal_600e74a97f5f8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426558/normal_604b390345595.pdfIn PDF document text
    • https://risovokoxenixe.weebly.com/uploads/1/3/3/9/133997247/bufejanasituvew-kapopuxoturup.pdfIn PDF document text
    • https://pejifivoriruruk.weebly.com/uploads/1/3/4/3/134314693/4b43fa6eb3edbf.pdfIn PDF document text
    • http://dfwshootersupply.com/syfy_shows_2020y6bnt.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://18b09f4e-de4d-4c1b-9fe6-be55c63b1c00.filesusr.com/ugd/cd81e9_f2305234c1724577a9a0063cfb41244f.pdf?index=trueIn PDF document text
    • https://f395d2f2-f939-483b-815f-81062d4747ff.filesusr.com/ugd/be2697_f0c56ff1e20e42c2b1285b0dcc959467.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/77793def-29af-4698-aa18-f3912f3c690a/power_and_politics_in_the_workplace_ppt.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/93e72c7d-31c1-480c-8d56-52af1f005458/zosotaw.pdfIn PDF document text
    • https://49432a94-54bc-4d13-9d12-ea41d731e1b8.filesusr.com/ugd/a7c689_e9fbc7eff104455d9ccb4797d53dd1be.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d1614a4f-7ffb-49e8-8d6f-161f85c80d44/reading_comprehension_test_for_senior_high_school_with_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3ad4ac6-f7c7-4e97-b41f-dce9b25ac2f6/mr_coffee_optimal_brew_replacement_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/442fd63e-f67e-4f7e-80aa-40c8e83d5103/pose_book_free_download.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED3B 5816 bytes
SHA-256: 3699ec455a98d6471be2f79c24bc6507db2ed30b4f86c27757d80441a985051d
font_01_sfnt_off0001011e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1011E 11256 bytes
SHA-256: 396f4d8b969833cd7c1f0864ee68f85d18780c405f22cdcbd5e1bb02d697fe1c