Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a9cc94cfeb967bf…

MALICIOUS

PDF

86.9 KB Created: 2021-05-03 02:26:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 922118c38ad136b49bf9c740509a2bff SHA-1: 412c55fd2c9c24609fa032e6cc6e50033cea6d64 SHA-256: 5a9cc94cfeb967bfb5d53fc3d5f94eab306dff03c1c7eb216033126007b34d81
186 Risk Score

Malware Insights

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

This PDF document was identified as malicious by multiple heuristics and an ML classifier, with ClamAV detecting it as Pdf.Phishing.Trojan. The document contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to malicious content. The primary URL identified is https://pelibifir.ru/strik?utm_term=uscg+medical+certificate, which is likely part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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/strik?utm_term=uscg+medical+certificate PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4380384/normal_605b817a07f13.pdfIn PDF document text
    • https://waretopaze.weebly.com/uploads/1/3/4/5/134529701/f4606ad9a.pdfIn PDF document text
    • https://jesasifewom.weebly.com/uploads/1/3/1/4/131453969/b1708e.pdfIn PDF document text
    • http://nitafibejuze.mygamesonline.org/modelo_brief_creativo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495843/normal_5fd63d013c141.pdfIn PDF document text
    • https://nusoselif.weebly.com/uploads/1/3/4/4/134470887/betewesera.pdfIn PDF document text
    • http://copyrightsupporthelpcenter.com/judo_basic_techniques4zqyj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369907/normal_5fe9069f780c9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374185/normal_60692000bad0b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384150/normal_5fd18f1350807.pdfIn PDF document text
    • http://onesmall.space/present_tense_verbs_spanish_worksheetnv8xj.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/5344f9b4-6f6e-47ef-b2a0-cfb700d76f6f/what_is_outline_in_writing.pdfIn PDF document text
    • http://diwavubodinaroj.myartsonline.com/kenmore_elite_dishwasher_665.127.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a176769a-6e21-4c77-9685-540b4185287a/stairway_to_heaven_chords_uke.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0bf606a1-3370-4a84-85bf-d89e672730a6/78460787638.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/21efdada-a3a3-4752-aaa6-eb1359f35e1d/maytag_front_load_washer_neptune_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc873afc-862e-47f8-a8c1-b8723676dec3/81385227425.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2198f59b-5394-43a1-a280-a6f88affd394/carl_rogers_on_becoming_a_person_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2992fa8-ec88-4e7e-9748-bd32a92e149a/history_of_economic_thought_book.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_off0001162a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1162A 5332 bytes
SHA-256: 136ea230a32f9bd70902eaee13bc54525a0d879b0f5d3366ebcff5ef0f670689
font_01_sfnt_off00012831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12831 11164 bytes
SHA-256: 686a88a6833a6a3792a6b296037d1fb0d2979f49fc5126bf9f944e8d9f461457