Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4f6aa85fb567815…

MALICIOUS

PDF

80.5 KB Created: 2021-05-22 03:11:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: b660a5d2a3ec248a4d4427d457ae1d4e SHA-1: a9d1ec58e95e0065fc6319f4b8bb7edfebfee74e SHA-256: c4f6aa85fb567815bb7de4a8db41cc9b1031fa1476ba0f00c2e9b0feb16d7336
232 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://crophysi.ru/strik'. Additionally, a 'SE_CLIPBOARD_COMMAND_LURE' heuristic indicates the document instructs users to interact with command-line tools, suggesting an attempt to execute further malicious actions. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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
  • 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://crophysi.ru/strik?utm_term=make+windows+7+iso+bootable+usb+rufus In PDF document text
    • https://sozetodu.weebly.com/uploads/1/3/4/2/134265488/jutapototimimelelo.pdfIn PDF document text
    • https://fenemonefozu.weebly.com/uploads/1/3/0/7/130739495/3213c5cced314e.pdfIn PDF document text
    • https://diwuxofemuji.weebly.com/uploads/1/3/1/4/131407179/derimupapafiveror.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370073/normal_601e066f64371.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381532/normal_6005cdb023bbf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413976/normal_5fd08d426a88b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497646/normal_6028e99037e6c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365634/normal_6034074d3156f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366666/normal_602467b23bbfa.pdfIn PDF document text
    • https://luwuruguvuwotom.weebly.com/uploads/1/3/0/9/130969706/jotemomix-jomed-momoxogo-kajudapatuwaf.pdfIn PDF document text
    • https://punepisisu.weebly.com/uploads/1/3/4/7/134724768/2119983.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417141/normal_6015b9842f668.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402032/normal_5ff3e39ce9bc6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380531/normal_6050fcef88789.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/sesijesule/evh_5150_iii_50w_6l6_vs_stealth.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/13743354-efa8-4eef-b1a0-25cf6cc1f76b/sawubizinusojetesi.pdfIn PDF document text
    • https://s3.amazonaws.com/zarelusipofox/36862579208.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1bb11458-a86a-4891-b69a-c8c0d2db8c46/50984709986.pdfIn PDF document text
    • https://s3.amazonaws.com/gagagakigibapo/escape_room_answer_key_level_30.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aac102ce-ba5e-4161-8b13-e5ddcd36992f/download_doubledown_casino_codes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2fb2601e-5b0b-435c-870a-cbcd06645685/pakisonenepes.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE45 5164 bytes
SHA-256: 419cc5312fa7aeb3898004cb861ecf1e6431eaadbdb403ea6f6db20626f1594c
font_01_sfnt_off0000fffd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFFD 11244 bytes
SHA-256: a82630c645bfb6cae0a50928cfc94fb1c67d40fe85e3613003d66992072c770a
font_02_sfnt_off00012693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12693 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176