Malicious PDF — malware analysis report

Static analysis result for SHA-256 51b53044a40c64d7…

MALICIOUS

PDF

103.8 KB Created: 2021-03-19 20:12:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 0112e5be689b344d078549b8a606ef4f SHA-1: 02185abe4ae3a8cb04b3581843504e319967e3f6 SHA-256: 51b53044a40c64d70b4a913e112dbf13dcae19d555d3fac5247cd8c50e2d719a
184 Risk Score

Malware Insights

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

The PDF was flagged as malicious by multiple heuristics, including a critical alert for linking to known malicious redirector infrastructure. The embedded URLs, such as dafemum.ru, suggest an attempt to lure users to potentially harmful sites. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a phishing or malware delivery attempt, likely distributed as an attachment.

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://dafemum.ru/award?keyword=mini+jet+engine+design+pdf In PDF document text
    • https://cdn-cms.f-static.net/uploads/4408463/normal_6052b3a8e63f6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417213/normal_6017c902c9a1f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412758/normal_601fd49c92eee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451205/normal_600e994018ae9.pdfIn PDF document text
    • http://bbbbbbbbeeee.space/ledojazuzuzuwunisenams8uz.pdfIn PDF document text
    • http://inmyshtangen.xyz/maplestory_m_buccaneer_skill_guiderosd2.pdfIn PDF document text
    • http://koolmaxt.online/gojoberujedlnm5m.pdfIn PDF document text
    • http://particuliers-societegenerale.xyz/subterfuge_make_a_sentencevch1j.pdfIn PDF document text
    • http://italywom.space/870477306672jdrq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475392/normal_602fa21def747.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369774/normal_6044ef5c61598.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450139/normal_6044729f6cadf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368478/normal_601bafeb9bdbe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485162/normal_6044caafb754f.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/0d26efea-e9a0-4896-b4d1-af6fd13ff245/my_vizio_tv_has_sound_but_no_picture.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bc6f091f-de73-4171-9c8d-f7369be68e7b/98136325786.pdfIn PDF document text
    • https://s3.amazonaws.com/lorugipopuxe/kallax_shelf_unit_assembly_time.pdfIn PDF document text
    • https://s3.amazonaws.com/belopudevuzuza/nujetiku.pdfIn PDF document text
    • https://s3.amazonaws.com/wajibile/zakife.pdfIn PDF document text
    • https://s3.amazonaws.com/juvosi/sainik_school_nalanda_admission_form_2018-_19.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5d0cfbe7-b32d-4fcc-98ed-189d0ed7cd01/39603646122.pdfIn PDF document text
    • https://s3.amazonaws.com/datarofapakil/wifavovibinometanumifo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c5c9f58a-6f22-4fef-81c3-ce664582bc41/42775441128.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ce5cd9a-330c-454b-aaa4-49076f17d3bb/arduino_projects_for_kids.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00015aef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15AEF 4952 bytes
SHA-256: afc0c34cd9a8ccccc65246144bc3bc6eb5cb310401c77153d944b52653b43fe8
font_01_sfnt_off00016bf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16BF9 11340 bytes
SHA-256: d8839531224a524cfd1ecfb1d8b01c8ee3daa188ad1782f8b3f460fe75f0693d