Malicious PDF — malware analysis report

Static analysis result for SHA-256 41e5da926ecef5f6…

MALICIOUS

PDF

76.1 KB Created: 2021-03-12 17:40:39 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 042509774c822449ce198acfb7704d76 SHA-1: 261f97fdda5ec960f11ccc3598726ae8db79820a SHA-256: 41e5da926ecef5f63cfb1041583479a12c3937295065cc56a84b22cea307d3f8
126 Risk Score

Malware Insights

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

The PDF file contains heuristics indicating it is a link farm hosted on disposable domains, with a high ML score and ClamAV detection for phishing and trojan activity. The document body, though heavily obfuscated, suggests a lure related to 'Mphasis aptitude questions and answers pdf'. The embedded URLs point to potentially malicious or unknown domains, suggesting the document's primary purpose is to redirect users to a malicious site for further exploitation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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/123?utm_term=mphasis+aptitude+questions+and+answers+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4501804/normal_601c98d1572d9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4494429/normal_6011b4b37e048.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4454045/normal_5fcae50569494.pdfIn PDF document text
    • http://letinebab.mywebcommunity.org/8510766014.pdfIn PDF document text
    • http://wepijafiguwenan.mywebcommunity.org/how_to_program_boss_gt_1000.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458628/normal_6042d1ad3f23e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/c090e031-85af-4a0c-9019-fb82139b4709/how_old_is_lyra_blair.pdfIn PDF document text
    • https://s3.amazonaws.com/verirejon/9166099710.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9833d11a-bfc7-435b-b842-c110ec918bad/how_to_wear_a_navy_blazer_with_jeans.pdfIn PDF document text
    • https://s3.amazonaws.com/xijuxosisomuna/98633296725.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8a80ecb3-a4bf-4fc9-ad86-64676b7b627b/95331362972.pdfIn PDF document text
    • https://201a0bc5-0eb3-4135-8969-828875a6b07d.filesusr.com/ugd/607883_0dd3dfdba86d407cb59d4d6e56f3420e.pdf?index=trueIn PDF document text
    • https://73e25548-3913-4bbb-aa69-a1b25f69568d.filesusr.com/ugd/cece23_7f0a39e9c06f4b30a05668fcf9b8e97c.pdf?index=trueIn PDF document text
    • https://31c8a3d4-0132-49f1-a04f-09c79d03e01f.filesusr.com/ugd/a4da84_97086154735546d9988056ede754b16e.pdf?index=trueIn PDF document text
    • https://ce2645ba-e89a-43d5-afff-5c0150757291.filesusr.com/ugd/c63dba_80fbd497b208463db1d8c7a6ef284e31.pdf?index=trueIn PDF document text
    • https://e31b828f-dd5d-4b35-abba-5777d5fc2ed6.filesusr.com/ugd/56a8cc_334c8bd69e7a4adca8fc4d58b72164ba.pdf?index=trueIn PDF document text
    • https://3c2b787d-8465-4662-bdcc-bf736d584291.filesusr.com/ugd/8760e7_2c97a3e3d17f4e49ba96e68dc7faa460.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/046657f1-69e8-4cab-9a46-72b243314b37/tokifozivaramanuxa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4ad9f45a-820e-4d11-b563-1871df74755e/33940454471.pdfIn PDF document text
    • https://s3.amazonaws.com/sixolose/best_small_home_theater_speakers.pdfIn PDF document text
    • https://937a8a2d-b41a-4163-aff8-eda6db263557.filesusr.com/ugd/21e6f2_c0de01e85ad246d18ae08c64c5bb2567.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_off0000ec3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC3B 5320 bytes
SHA-256: 65c58ff2ce2b7ae93e0231ba68c1c8a4da7ad816ebb56aed99e509bfbc1fb9e3
font_01_sfnt_off0000fe64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE64 10620 bytes
SHA-256: 808dca21e4a9e59078fb6aa04b7262722cd49073ef9ff7ff8c836fe307959a39