Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ed5bf0db1d766f1…

MALICIOUS

PDF

70.7 KB Created: 2021-05-23 02:41:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: eceae75f4a991e56e9bd77fd37e488a2 SHA-1: 560c0f6dc56a60ca250fa41506b5676e7e44c1d8 SHA-256: 1ed5bf0db1d766f10019701d35e616f5540fbaab5b5030f933020bcc85c3b32c
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting services, suggesting a link farm designed to distribute malicious content. The heuristic 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate a large number of links, with one pointing to 'https://jacksth.ru/strik?utm_term=cat+c15+repair+manual+free+download', likely a lure for users seeking a repair manual. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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://jacksth.ru/strik?utm_term=cat+c15+repair+manual+free+download PDF link annotation
    • https://litemavokof.weebly.com/uploads/1/3/1/8/131871991/tazomoxal.pdfIn PDF document text
    • https://vifefafu.weebly.com/uploads/1/3/4/8/134876142/7228994.pdfIn PDF document text
    • https://noxajigaja.weebly.com/uploads/1/3/4/6/134698193/xawidix.pdfIn PDF document text
    • https://norofuzalugegok.weebly.com/uploads/1/3/4/8/134882219/8590794.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4498997/normal_5ff2772041125.pdfIn PDF document text
    • https://nopiviwefimak.weebly.com/uploads/1/3/4/7/134708781/gonokelegi-rorunekisun-wujut.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379359/normal_602954a18186d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4376878/normal_60007960d3caf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424933/normal_60615a9ed6c5e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411921/normal_60174cf0912b9.pdfIn PDF document text
    • https://kolerekum.weebly.com/uploads/1/3/4/3/134350376/1a3cceb215267.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476766/normal_606e9c62376a9.pdfIn PDF document text
    • https://rozinezo.weebly.com/uploads/1/3/1/6/131636990/fazewesobozadidawur.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500183/normal_5fe791806b3bc.pdfIn PDF document text
    • https://wobanavemo.weebly.com/uploads/1/3/4/0/134096337/sujuwuzede_loxiwa.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/ec7745e9-bc44-4634-a197-ca754962a3a4/89346110431.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f43c2e1-0a51-41e9-a3c6-1f89687a102e/68818078270.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c050a18-fef3-41e4-b6dc-f74ef2137332/ms_access_2007_tutorial_free_download_in_hindi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/025b4246-e7c1-446b-be5e-ea7cdc68c8bc/90635574504.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7f6aa78-f888-4ba6-845d-454028594bf1/impact_draw_furries.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/35cd68e8-b27e-4407-95fc-52decfd6393c/ruxapobanaxotelebarilep.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f337a50c-2612-4bea-8da1-c05ff5a55f9a/donoxexil.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_off0000d835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD835 5296 bytes
SHA-256: ee6733345f0a3c2c46f105fb3b410789374b2c1fa601d749e9a1738e06db9d4a
font_01_sfnt_off0000ea39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA39 10344 bytes
SHA-256: d36e8e99a072137ad2f05963fd3f4979715f490f32ec08dc18a2e1a7bb38d9f7