Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e86231876582bcc…

MALICIOUS

PDF

111.5 KB Created: 2021-03-24 21:58:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 81980001b32e1d23be3290177e623ee2 SHA-1: cdcf48e037cfa202d8c063f6785dac7d3d5d186c SHA-256: 5e86231876582bcc93564a16a69848e7f1ccf416bd4d1548f7202aadf792e04c
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable domains, suggesting a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://pelibifir.ru/wix?keyword=complex+circuit+problems+worksheet PDF link annotation
    • http://dakisemakegag.sportsontheweb.net/dan_brown_robert_langdon_books_movies.pdfIn PDF document text
    • http://mazikopipovix.mywebcommunity.org/books_of_the_bible_old_and_new_testament_word_search_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464068/normal_6031af016ea0e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446388/normal_5fe880ac20cee.pdfIn PDF document text
    • https://sorudexene.weebly.com/uploads/1/3/1/3/131384015/8004887.pdfIn PDF document text
    • https://mojijunu.weebly.com/uploads/1/3/1/0/131070220/46539039614.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421940/normal_60304f2d2a5a2.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4445326/normal_5ff5dd0eb7b0e.pdfIn PDF document text
    • http://kilijosizujowo.medianewsonline.com/dawokivurubopumulukoru.pdfIn PDF document text
    • https://gonudelosake.weebly.com/uploads/1/3/4/7/134750135/9318183.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380881/normal_601d5b73e2e63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480402/normal_603f5f7e61902.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://3c86e5df-9a55-47dd-9d5b-c207b25ec6cd.filesusr.com/ugd/72bf36_8ab2cc3194c44d7a8e6887ecdd4abb00.pdf?index=trueIn PDF document text
    • http://pesetunal.onlinewebshop.net/bamasutotivimi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/551ef818-091f-4981-99df-330d2ea4544d/jumbo_universal_remote_control_61959_manual.pdfIn PDF document text
    • https://9b704b87-3668-414c-a24e-b30400fe0e33.filesusr.com/ugd/51c472_6d2d59d0eaee482396220e76bb15e3ed.pdf?index=trueIn PDF document text
    • https://bb74f61c-7045-47bf-9a7e-968101ee373e.filesusr.com/ugd/81ef4b_c59e57cf2c4c44ac99e20d31d20412c8.pdf?index=trueIn PDF document text
    • https://171e2b11-24ea-4535-acac-f971ec821c4b.filesusr.com/ugd/a07927_0a6887be2f48496eade3aed73ebdc44e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/826219f3-bf9f-4990-a5b0-40f9c65a74f8/dijima.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015668.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15668 2828 bytes
SHA-256: b7f317aa0f29cd34df008dc84d8f376d2685882a57a4a5cd0d86477d0adf885a
font_01_sfnt_off00016063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16063 5232 bytes
SHA-256: 5a3b2f14bcd1c772bf1241f066d27b1639c87a41a3d50057607cc2652bf07bb8
font_02_sfnt_off00017210.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17210 11692 bytes
SHA-256: 99b7b15d928f18c15b6bedd80102872a31957e9145b55fd8b31cad36c76a6739
font_03_sfnt_off00019920.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19920 16240 bytes
SHA-256: 22e3a265051de049fcf7fb23205ac081a5706510055ebc504bc7ee755b3f2d84