Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6db703ae02d2912…

MALICIOUS

PDF

70.7 KB Created: 2021-02-16 12:11:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: eb8cf5d403421f01aed92ec5c65096bf SHA-1: 39bc7cb14593f2e6cda0bd6b3781f73f965208ab SHA-256: f6db703ae02d29120384bb0e3d2133cb36815d37a08807368bcb447694665453
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with several pointing to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the presence of numerous links suggests an attempt to lure the user to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://yafferge.ru/strik?utm_term=call+me+by+your+name+script+to+screen In PDF document text
    • https://cdn.sqhk.co/kigifadarija/eDjfidW/homeschooling_in_nc_curriculum.pdfIn PDF document text
    • http://lovelyhouse.online/9433178003c1uni.pdfIn PDF document text
    • https://bonifivudinuf.weebly.com/uploads/1/3/4/3/134305406/2f343b5f.pdfIn PDF document text
    • https://cdn.sqhk.co/pajokiman/xPjhFic/replacing_hard_drive_windows_7.pdfIn PDF document text
    • https://cdn.sqhk.co/nutewakizi/Ryzidhj/2006450268.pdfIn PDF document text
    • https://cdn.sqhk.co/salenasova/hggFJhg/pin_code_of_kasak_circle_bharuch.pdfIn PDF document text
    • http://wow50.pro/bolanawowajoxupimuvojakodcvzmq.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449768/normal_5feff4cd98d22.pdfIn PDF document text
    • http://mmmuuuue.space/sebovu41w4b.pdfIn PDF document text
    • https://cdn.sqhk.co/zibomevuguli/gjmEmih/10130037352.pdfIn PDF document text
    • http://podarokinsta365.site/spelling_numbers_worksheethnhd8.pdfIn PDF document text
    • https://cdn.sqhk.co/momajuxu/gjf0qjb/zain_online_recharge_ksa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wivufaw.epizy.com/rocketman_2019_parents_guide.pdfIn PDF document text
    • http://fugirar.epizy.com/84205148685.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_off0000d7e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E0 5228 bytes
SHA-256: 9b1a954dcd2a8da13c8c0f654b130aa44cef3712c20c11f5e8c964bda6bf3e09
font_01_sfnt_off0000e993.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE993 10700 bytes
SHA-256: 98831650bd154df90a449617b58eb8175696dd50f58ecc53d2538790bdf8fcd8