Malicious PDF — malware analysis report

Static analysis result for SHA-256 e61e7ec900cc80d0…

MALICIOUS

PDF

80.0 KB Created: 2021-04-02 20:48:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 83e9907c6a20818a6f3c02ef40fbb6d4 SHA-1: 4e1ce0ede5fb5b7952275bcc00d1aef77dff21df SHA-256: e61e7ec900cc80d0cad5c4672e7ac5b546632bc932467f93955531b50a3e1370
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spamming operation. Some links point to other PDFs, potentially chaining malicious content. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

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://resalured.ru/award?keyword=telugu+boy+names+starting+with+s+pdf PDF link annotation
    • https://voledobaseju.weebly.com/uploads/1/3/0/9/130969813/1587412.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4382629/normal_5fca6de7da57a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4472491/normal_5fee111a60f1b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4366958/normal_600365e90b706.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4463262/normal_5fcb4e116226c.pdfIn PDF document text
    • https://vadizomozizi.weebly.com/uploads/1/3/5/4/135400682/1bbb7bfe9a18.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489244/normal_5fc88fc73fa9c.pdfIn PDF document text
    • https://tivenudonokokom.weebly.com/uploads/1/3/0/9/130969369/8199328.pdfIn PDF document text
    • https://jigupeditu.weebly.com/uploads/1/3/1/3/131380623/31576de.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414153/normal_60625ea3abf24.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/pegebunov/oh_k_bubble_sheet_mask_review.pdfIn PDF document text
    • https://19095d9e-104b-4983-ab45-6a52d868d4ec.filesusr.com/ugd/87ad98_f11e3b2141b040119265aa54a5bb3569.pdf?index=trueIn PDF document text
    • https://78151a86-a557-4e49-81aa-a2539eea45c7.filesusr.com/ugd/204f4f_d6783bdd45d14f37b5dd7f08d560780c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wozoxub/vagaxu.pdfIn PDF document text
    • https://f33eab34-52c4-4f1b-91c9-7c5ec1255b8f.filesusr.com/ugd/9d0374_00dd5e3e3abc4f7eba0076fd35038e47.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dinilederu/11067884346.pdfIn PDF document text
    • https://84daacc9-7e90-4c5d-b1ed-526950900c49.filesusr.com/ugd/73f3b0_887134bcab7b4c429d6ab81dbca5cd3b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rufonali/omw_platform_advisor_login.pdfIn PDF document text
    • https://1a9cd40a-f0d6-44d4-a143-19288280ca2b.filesusr.com/ugd/7a13df_e59e60485c0041c4805e8f7813d93dab.pdf?index=trueIn PDF document text
    • https://7fe1f042-206b-4735-a408-f56337efeeb4.filesusr.com/ugd/d34b51_3676e21ec9824714a637844fd50e88a7.pdf?index=trueIn PDF document text
    • https://4fe85328-8dbf-40e9-afa8-2c8d6ff8a9c8.filesusr.com/ugd/9c0842_4a8b69963b0541198972dc114f9367ff.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_off0000fa8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA8C 5736 bytes
SHA-256: 60380ff6f790812765b054dc75d4803980a287c33ae2f3ecc255d8dc3dc72921
font_01_sfnt_off00010dfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DFE 11004 bytes
SHA-256: 937630acec7be195ec4b4cd18eb4b7cc5160cf00ab875674962236ac406fe491