Malicious PDF — malware analysis report

Static analysis result for SHA-256 5fde757629d45c20…

MALICIOUS

PDF

78.8 KB Created: 2021-05-27 03:43:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: 0adda393c2bd7395e8c6200ee7bd8e09 SHA-1: 4707a6252c4613df338df65af4b6f9375b18f250 SHA-256: 5fde757629d45c204aa2350e980423a52b51ac80fafa9da636d50c8102537119
244 Risk Score

Malware Insights

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

This PDF document contains a large number of embedded links, many of which redirect to external websites. One critical heuristic indicates that the PDF links to known malicious redirector infrastructure, specifically `https://dafemum.ru/strik?utm_term=download+nitro+pdf+64+bit+free`. The document body, though heavily obfuscated, appears to be related to downloading software. The presence of numerous links and the malicious redirector suggest an attempt to lead the user to malicious or unwanted content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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=download+nitro+pdf+64+bit+free In PDF document text
    • https://nowitijot.weebly.com/uploads/1/3/4/7/134716658/777649.pdfIn PDF document text
    • https://sivipamekan.weebly.com/uploads/1/3/2/6/132682587/433974.pdfIn PDF document text
    • https://gagoxesuv.weebly.com/uploads/1/3/2/6/132681450/fe9c2.pdfIn PDF document text
    • https://vepemetamat.weebly.com/uploads/1/3/4/3/134354227/8580820.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411500/normal_60531b33cb63b.pdfIn PDF document text
    • https://toxosujaduwo.weebly.com/uploads/1/3/0/8/130874389/8b75d603fe1c14.pdfIn PDF document text
    • https://zixavuxo.weebly.com/uploads/1/3/1/3/131398386/7429677.pdfIn PDF document text
    • https://bapumuper.weebly.com/uploads/1/3/1/1/131164114/ligenupetapobibudu.pdfIn PDF document text
    • https://renepavavoz.weebly.com/uploads/1/3/4/0/134012855/29d02e.pdfIn PDF document text
    • https://razitesewiwi.weebly.com/uploads/1/3/2/8/132815022/3431674.pdfIn PDF document text
    • https://dewufore.weebly.com/uploads/1/3/4/8/134857007/2919067.pdfIn PDF document text
    • https://xenolato.weebly.com/uploads/1/3/4/8/134868471/3870229.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491926/normal_60431a6b238da.pdfIn PDF document text
    • https://zuwasaroniw.weebly.com/uploads/1/3/1/3/131380739/kexukesun.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/6671dd51-a94c-4df6-9364-3a6c02aa9dc6/gudizarisetobanewixob.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a32903ac-99ef-45c5-ac93-0b1cf0b16e7b/jesedimudapoxukuruzot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/40fe999d-480a-4248-b19e-5c6841121026/garmin_gpsmap_64x_gps_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7945edc-54ed-4217-b23f-70116ce0c891/tirunosajojukuredavi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d68a0f5e-6340-40b0-96b6-3accf1adb094/how_to_play_red_dead_redemption_2_for_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/015fe16d-3352-42f2-ad2e-53da59fa4117/88440006058.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_off0000f3a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A0 5332 bytes
SHA-256: 6ed2a582b7cad124b4bbaf6362c0864e68d733368ee2704f46baeba05716be88
font_01_sfnt_off000105e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105E7 11816 bytes
SHA-256: 6d17d9b58552bfc35e5c3dc7158fe0e8a5f8b500d38440ee66bca3888d4709c5