Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbd34fec81f6487d…

MALICIOUS

PDF

92.1 KB Created: 2021-04-12 23:27:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 66d8ebcca0572292fbb7206daacb7e40 SHA-1: b7cba513c95821f212d69759f55a647c7e690466 SHA-256: dbd34fec81f6487d9576fff7e762fd25737f404717694ead6b2c364b83915056
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to disposable hosting and some leading to known malicious redirectors. This behavior is indicative of a link farm designed to distribute malware or phish users. The ML classifier and ClamAV detection strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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 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.
  • 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/strik?utm_term=saint+of+the+firmament+ff14 In PDF document text
    • http://datab.vip/bulmershe_school_uniform_shoprej3v.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448980/normal_60339dd0861ed.pdfIn PDF document text
    • http://parhelifrl.space/community_helpers_worksheet_kindergartenzmhnm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455659/normal_6026c5633ddfd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4498345/normal_5fd2f91b21204.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371786/normal_60150d28ec8ee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365628/normal_5fd61c9b484b6.pdfIn PDF document text
    • http://botarim.22web.org/speak_up_magazine.pdfIn PDF document text
    • http://jevufoduxixan.22web.org/personal_finance_crossword_answer_key.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://kugunimekuxaf.epizy.com/powuxexilitovino.pdfIn PDF document text
    • http://weniled.epizy.com/64639261902.pdfIn PDF document text
    • http://gafoxipebivama.rf.gd/bsc_1st_year_books_in_english.pdfIn PDF document text
    • http://lawazujazigefon.epizy.com/47133548545.pdfIn PDF document text
    • https://6558ac43-984d-4e3a-97a1-dec8860611ed.filesusr.com/ugd/c73740_23d89a548b3c47c2bb659c67b4c4f404.pdf?index=trueIn PDF document text
    • http://zawofepak.epizy.com/43816146461.pdfIn PDF document text
    • http://gokutirimavav.rf.gd/how_to_fix_samsung_top_load_washing_machine.pdfIn PDF document text
    • https://92e0cadd-ca3c-497d-ba7d-1aece6ee6da0.filesusr.com/ugd/008e52_98f5695fbf8c454493e7d8a38c9869c7.pdf?index=trueIn PDF document text
    • http://dasiletu.epizy.com/all_business_letter_format.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD26 6564 bytes
SHA-256: feac56802bb390acd5525d7c9883e47671b0dd7b575605fe85fdc6883c80eb0e
font_01_sfnt_off0001135f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1135F 5040 bytes
SHA-256: 3c3ef25adef6e7134f23b812636e98c30d5a113c53bcc6b5e614b4d52b610944
font_02_sfnt_off00012463.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12463 12112 bytes
SHA-256: 894183bdcbd36f49cfb26b3aba2a137f29d6ac658641cc221da9d11d0a213afc
font_03_sfnt_off00014dbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14DBC 16160 bytes
SHA-256: 71fec8a3adfe41455811528c654ef740a0d97889ddd19e39e153b04b7507b7f0