Malicious PDF — malware analysis report

Static analysis result for SHA-256 53bd98235efe93db…

MALICIOUS

PDF

172.8 KB Created: 2021-05-27 21:26:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 3445fbf2b2eac58c88cb1bba99cef68c SHA-1: 78df56a363f2ef7e31fbbb489b375306ee84e663 SHA-256: 53bd98235efe93db45e3279034cde702b8c7eabe0a893d34e34af00fb060461f
184 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with a critical heuristic firing indicating redirection to known malicious infrastructure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were extracted, the presence of many links and the malicious redirector URL point towards an attempt to lure the user to a compromised site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=android+studio+3.+0+release+notes In PDF document text
    • https://cdn-cms.f-static.net/uploads/4417220/normal_6029a088be08a.pdfIn PDF document text
    • https://zobanegasub.weebly.com/uploads/1/3/1/1/131164549/vinusidi_wevowixigufuxa.pdfIn PDF document text
    • https://wesudami.weebly.com/uploads/1/3/4/8/134881188/busatuxasim.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455390/normal_5ff7735621580.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381531/normal_5fef8123e018a.pdfIn PDF document text
    • https://xanilavobug.weebly.com/uploads/1/3/5/9/135959945/862494.pdfIn PDF document text
    • https://pibazafefudo.weebly.com/uploads/1/3/0/7/130776509/nekax.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471706/normal_5fd9bf0b5a201.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491669/normal_60633865778f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392444/normal_605850581ebe5.pdfIn PDF document text
    • https://gumopokexu.weebly.com/uploads/1/3/0/8/130814161/6175823.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377114/normal_6007b49b875ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501804/normal_606bbbc5688a4.pdfIn 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://uploads.strikinglycdn.com/files/ee345673-4517-46c2-bda9-8916f08dfbf6/excel_vba_pass_multidimensional_array_to_function.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8b5bd463-dcd0-45dc-8e9a-94205f8f5abc/ms_project_2013_download_64_bit_with_crack.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9361c776-f8f8-4954-bb88-055feeed79fc/fenokuzikotugawefa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6dee94be-ca5b-4520-9cb7-d95a18f12b7f/midsummer_nights_dream_analysis_questions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd22d2a4-b17f-48a9-9d71-b7150e6a6a8b/journal_entry_examples_learning_accounting_the_easy_way.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c84bc168-30c7-4ebd-897d-3c4d65d792fd/tuvalibidejetezorov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9f225a4d-981f-4936-bfcb-af94665232d9/motebeluleseromimexitumiw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6574c942-072a-410b-8ff8-8ddc9657a990/16153003166.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00025c0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25C0E 5028 bytes
SHA-256: 4d7f113d520aa9f25580659eece550c7459349fd6c3064b953697dca20eb78a6
font_01_sfnt_off00026d2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x26D2A 12344 bytes
SHA-256: 64a240d12d55b61f86bab9432748db12fac21e43c6b435316d305ab080588db0
font_02_sfnt_off0002972c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2972C 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2