Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec5d3975d395a583…

MALICIOUS

PDF

111.7 KB Created: 2021-03-29 06:18:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: f791e1ec7cdc1589fa076d46c9296d52 SHA-1: 3b2bd56c442d705eb57f5ec0c11d4bc954647a2e SHA-256: ec5d3975d395a5834d22d0adf0136cba3103693409be83e6448d00264dfd57ab
226 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many hosted on disposable domains, suggesting it functions as a link farm. The heuristic 'SE_LOLBIN_RUN_COMMAND' indicates potential execution of commands via embedded URLs, and the presence of external URIs points towards a phishing or malware distribution attempt. The document body is heavily obfuscated and unreadable, providing no direct clues about its content beyond the file metadata.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://mezovuduw.ru/award?keyword=anualidades+anticipadas+ejercicios+resueltos+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4471114/normal_6046727145b32.pdfIn PDF document text
    • http://itsamorem.com/zorunibijixazelabige2beyv.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409798/normal_5ff5b5266313e.pdfIn PDF document text
    • http://fitnesspack.net/movafagerumoporxioj.pdfIn PDF document text
    • http://thestablestl.com/pet_sematary_1989_parents_guide8fvrp.pdfIn PDF document text
    • http://steblin.pro/kenmore_gas_range_790_manualssifn.pdfIn PDF document text
    • http://fontawesome.iohttp://fontawesome.io/license/In 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
    • https://s3.amazonaws.com/rupatojuko/how_to_apply_s_curl_activator.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2706ab2-612a-4bf9-a49c-f5dd9ba82173/stewart_calculus_early_transcendentals_table_of_contents.pdfIn PDF document text
    • https://s3.amazonaws.com/mexijegedakol/nazexapomamizolifod.pdfIn macro / runtime command snippet
    • https://uploads.strikinglycdn.com/files/79f9e05a-e9a9-41e9-9d33-675b3752d4df/99352292162.pdfIn PDF document text
    • https://36425c1f-c329-48aa-845d-1f8252cb45c8.filesusr.com/ugd/01d500_bdcc57a490084455a4ff98a0eefe5586.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/debb7978-71d3-4598-a4e1-fe0c046cf5c8/is_600_a_good_sat_math_score.pdfIn PDF document text
    • https://s3.amazonaws.com/wifiduxezo/88891119204.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92ea74f6-cf4c-4245-8cac-af492b05376a/tesudemapopuzalolomojev.pdfIn PDF document text
    • https://88211235-bf86-4d40-a6ec-a052db2f682e.filesusr.com/ugd/94e5ef_1da4a21455ed4a06965553affe018486.pdf?index=trueIn PDF document text
    • https://84daacc9-7e90-4c5d-b1ed-526950900c49.filesusr.com/ugd/73f3b0_68f45c039adc4b64a55c5dcb990bd4e9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/67d4ce51-f7b5-4285-8d14-a4764df57cbb/jekaxetemexemiponixovanu.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
    • https://uploads.strikinglycdn.com/files/bIn macro / runtime command snippet
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015437.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15437 1596 bytes
SHA-256: 6e3d9c77d6f70b82240b1cd20415211894c16d7ff99d080eaa7d69371a6b33a5
font_01_sfnt_off00015c32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15C32 5096 bytes
SHA-256: e8507be3c301ed4bba5e4c319e9049405fae42633ea2bc6bec4d7d1bfab79dc9
font_02_sfnt_off00016d87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16D87 2472 bytes
SHA-256: 8d928ffe8b5ef4272cb7c2e8514909148318c05297d00204740e2f74bba5e55e
font_03_sfnt_off000177c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x177C4 12576 bytes
SHA-256: 75076ea3117a7727093a1fde5d4358cc97cc5cb287d929fc044e28f34380398f
font_04_sfnt_off0001a073.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A073 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c

Open this report in the interactive analyzer, or submit your own file for analysis.