Malicious PDF — malware analysis report

Static analysis result for SHA-256 b511eb53c67447fc…

MALICIOUS

PDF

76.6 KB Created: 2021-04-25 02:32:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: efc0dd4b3f496dfab8983536c378b247 SHA-1: 175963aabebba0965773ccb5b55cbd792b2ad9e3 SHA-256: b511eb53c67447fc52edeb312fe141217fd551a4a3f4599c29156cbd4ffe7c6e
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO spamming operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the structure and numerous URLs suggest it could be used to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://nipisod.ru/strik?utm_term=epson+wf+3540+not+printing+black PDF link annotation
    • https://cdn.sqhk.co/bulixanejad/hc8M1ii/96881417280.pdfIn PDF document text
    • http://duvazejezirofid.22web.org/barsaat_song_bestwap.pdfIn PDF document text
    • https://cdn.sqhk.co/fopujetoros/X6Fhgjf/gym_exercises_for_beginners_male.pdfIn PDF document text
    • http://movawizaxaxato.mywebcommunity.org/61394220215.pdfIn PDF document text
    • https://cdn.sqhk.co/bifoligi/7lpSrkv/30035981900.pdfIn PDF document text
    • https://cdn.sqhk.co/xejadukoxeta/mhevjjP/write_notes_on_iphone.pdfIn PDF document text
    • https://cdn.sqhk.co/ruxuvedije/cjghfhh/pinball_wizard_elton_john_tab.pdfIn PDF document text
    • http://suvuxivenorum.mypressonline.com/54927084909.pdfIn PDF document text
    • https://cdn.sqhk.co/mujawiru/geVifia/escaping_the_prison_henry_stickmin_wiki.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://takodibunogudas.epizy.com/tobofejegovi.pdfIn PDF document text
    • https://746420f6-3007-491b-ba72-fd43be5094e5.filesusr.com/ugd/277b62_45d46642aaf84e0ab16ea438ad3e6ff4.pdf?index=trueIn PDF document text
    • https://200c4c3d-185b-4246-b99f-f40cd7065c99.filesusr.com/ugd/3ed902_f561873e2d39498c9e1775c5f14fc57f.pdf?index=trueIn PDF document text
    • http://rodurepulawu.epizy.com/powebumowilup.pdfIn PDF document text
    • https://38c64f87-0506-4925-a3a1-425743e24937.filesusr.com/ugd/386d45_47bd5e34ceb7400f829488224870bfe1.pdf?index=trueIn PDF document text
    • http://rikonobawo.epizy.com/wedijanajejut.pdfIn PDF document text
    • http://piruxogijuba.rf.gd/wolutukoxona.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87fed9d1-448c-4d74-a9c2-faf6f621ed61/tuxafeza.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7c01875-5afb-40a6-9ab9-8e64bd2f8f38/76743099859.pdfIn PDF document text
    • https://7ef5d8b8-74ac-4e0a-b0a0-fa61ca6462a8.filesusr.com/ugd/23e9be_03e5822d57d2474ea743ffdffa79a377.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/0477f164-c655-4732-bf9b-82c04a398d90/how_to_silence_alarm_on_cyberpower_ups.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/260328c2-fcdc-4361-94cb-d4fe5d367486/dilurabuziluloru.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_off0000ea13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA13 5952 bytes
SHA-256: 78d124f93cfb948f0b2e3704239bff6c5d2d737865fee403575f3d150927ff84
font_01_sfnt_off0000fe8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8C 11272 bytes
SHA-256: b0e86a6898bdd016a8b5f0c00c74a0c34cd10cc8fea683454ead89a54f50f55f