Malicious PDF — malware analysis report

Static analysis result for SHA-256 867dbbef11c3756c…

MALICIOUS

PDF

77.5 KB Created: 2021-03-21 04:20:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 2793520c8c13f4a1bd3c0f59b471c67a SHA-1: 509b31c9af89ccaf48e42b05445113dee2ee9e36 SHA-256: 867dbbef11c3756c4e259413e9c72e3271ac07bcb368c29dd9668db5f587a8f4
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of embedded links, with several pointing to known malicious redirectors or disposable hosting. The primary malicious link identified is https://dafemum.ru/strik, which is likely used to redirect users to phishing or malware distribution sites. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://dafemum.ru/strik?utm_term=let%2527s+explore+diabetes+with+owls+chapters In PDF document text
    • https://cdn-cms.f-static.net/uploads/4425919/normal_605479afe2f78.pdfIn PDF document text
    • https://vojidejera.weebly.com/uploads/1/3/2/6/132695434/wedufik_xemobezafelupir.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369660/normal_6011832e9019e.pdfIn PDF document text
    • https://s3.amazonaws.com/zodererezuzuxi/kuzokule.pdfIn PDF document text
    • http://lorenbayi.com/83199576773kv1g1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470841/normal_60184e92ede00.pdfIn PDF document text
    • https://nabebumiz.weebly.com/uploads/1/3/1/4/131452902/sepupisawotoroj-wenizoginomob.pdfIn PDF document text
    • https://nokajavu.weebly.com/uploads/1/3/0/9/130969653/xuluraded_mevezakuvo_bopesakitis.pdfIn PDF document text
    • http://itanah.space/sabarawevumez464m5.pdfIn PDF document text
    • http://filozajerezabi.getenjoyment.net/59373611967.pdfIn PDF document text
    • https://s3.amazonaws.com/wixamupelinere/acceptance_speech_2._0.pdfIn PDF document text
    • https://gavuwexis.weebly.com/uploads/1/3/4/7/134772394/texovuneganivaxubujo.pdfIn PDF document text
    • https://s3.amazonaws.com/vufupu/g_shock_ga100.pdfIn PDF document text
    • https://s3.amazonaws.com/kakef/54688283036.pdfIn PDF document text
    • https://jamoxumo.weebly.com/uploads/1/3/1/4/131438684/2c4f6.pdfIn PDF document text
    • https://s3.amazonaws.com/dibedamoka/34740187911.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490128/normal_604159040367a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4494160/normal_5fcea15070c12.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wiloradakuno.onlinewebshop.net/which_book_is_best_for_civil_engineering.pdfIn PDF document text
    • https://9c43cb74-45e3-47de-9527-fda2e8336169.filesusr.com/ugd/af0aa9_88fa33c35f9e45ada0a4b4a688794cb9.pdf?index=trueIn PDF document text
    • https://3ff4c494-4984-418a-b709-7a5c611cca0a.filesusr.com/ugd/adbee0_42446d9e68d1434092576fca62fec6f9.pdf?index=trueIn PDF document text
    • https://413f70bc-0247-4a04-a3fc-eabb14e2b93f.filesusr.com/ugd/f18ee6_cea6f19dd0344c20ac93faf960b51ea8.pdf?index=trueIn PDF document text
    • https://1350f94c-8d6f-42b4-8351-24983ad6a49a.filesusr.com/ugd/4aae87_7219e9c479fc4e66866e9ea38c72508e.pdf?index=trueIn 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_off0000f077.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF077 5436 bytes
SHA-256: 50bc16645e40664e786264448ade98de5d96bb2ec246ff7dd1f55ae7260eec84
font_01_sfnt_off00010306.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10306 10996 bytes
SHA-256: 608cd315920c2273bf8980f5b3445600bf7aae3d93bfc79f0038e689247bced6