Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6c8575723ff8f9c…

MALICIOUS

PDF

76.8 KB Created: 2021-05-16 11:52:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 8dba6b2eb262eb1103d5515d225d17ac SHA-1: 25a0931e1df10ac032b232c25e60a8dded8e6819 SHA-256: d6c8575723ff8f9c34b2bd09f24dd91dc2e08cb97e8b3dffa794ff7dfb742759
194 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting it functions as a link farm designed to redirect users to potentially harmful websites. The document body, though partially corrupted, suggests a lure related to 'Relative pronouns worksheet grade 6', likely to trick users into clicking the embedded malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=relative+pronouns+worksheet+grade+6 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4387056/normal_6032d80e8e6a8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495413/normal_5fe2caeaf0467.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462993/normal_602c29387853c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379487/normal_60306d3b09d94.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464541/normal_6022875e7d11a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459794/normal_5ffa22f4ea4fe.pdfIn PDF document text
    • https://lijujizakivim.weebly.com/uploads/1/3/4/6/134634855/72c2e13e.pdfIn PDF document text
    • http://getsalon.xyz/bootstrap_glyphicon_icontompl.pdfIn PDF document text
    • https://bategasef.weebly.com/uploads/1/3/2/7/132712490/kesedigepufo-zabega.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410006/normal_60698192d8a3a.pdfIn PDF document text
    • http://avtoshkola-region26.ru/wd_tv_live_streaming_media_player_specsjyw9w.pdfIn PDF document text
    • http://reliables.ru/mikoposuwara5o9os.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404308/normal_5ffb21faeb1a0.pdfIn PDF document text
    • https://savakofanedekin.weebly.com/uploads/1/3/4/8/134872369/1433793.pdfIn PDF document text
    • https://lanuwoga.weebly.com/uploads/1/3/1/6/131637333/kekasagik_joxuzasosovorip.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/8c487e53-d6c9-441f-82cb-13fb7769adfa/kigutizalukezomipugigo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/caec015c-df30-41c4-abf4-4960dc61a750/gilenomobemoni.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d1f90331-7ac7-4dcc-b9ca-18ede5a5fcd2/what_are_some_examples_of_embedded_systems.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9c93eba7-3afb-4346-9d59-efaf98cac1a8/sefubanesaruzut.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fad0663d-e756-4925-b921-0468f6634d5e/dell_e7450_second_hard_drive.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_off0000ec70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC70 5600 bytes
SHA-256: 0f3f84d216457e2fdce6ddd5d35dae006039f37532d7404ac6d79711832716ca
font_01_sfnt_off0000ff98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF98 11228 bytes
SHA-256: 48509e9b15fd2b331b30fc4ae2d38924ce68a60d184e4704aaf2b4788dff3a7e