Malicious PDF — malware analysis report

Static analysis result for SHA-256 305804ba7a8cfd30…

MALICIOUS

PDF

76.3 KB Created: 2021-05-30 03:01:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 5e9921b5a25f8917be7128eebd5d93b6 SHA-1: 2436218aa0aafb4ec24dcf8aedd07ed2891c58c1 SHA-256: 305804ba7a8cfd30beb25d88dca2873f6ee81e52d2cfb85c15777744bbae6f61
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users. The primary URL, 'https://jottigo.ru/strik?utm_term=audio+converter+offline+apk', indicates a lure related to an audio converter, likely to trick users into visiting a malicious site. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://jottigo.ru/strik?utm_term=audio+converter+offline+apk PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4455670/normal_603b42d3518f3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455642/normal_5fc59acb2090c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481052/normal_5fecad802a690.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4459034/normal_60afe62294f30.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392867/normal_606d573c49259.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473445/normal_600662a42f0f0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473902/normal_5fdace605f34b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369327/normal_605a060a08090.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446377/normal_5fe82d64659f8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4418367/normal_5ffc1a78266c3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500432/normal_5fd7f8aa37d87.pdfIn PDF document text
    • https://fifejinokufo.weebly.com/uploads/1/3/4/8/134846395/333bdb4c98c0f28.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4455657/normal_60b13e44a46d5.pdfIn PDF document text
    • https://panodetis.weebly.com/uploads/1/3/4/6/134669877/fukirivawadujafuku.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388424/normal_5fd793c660b9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4527357/normal_603d5f49ca1bc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4408712/normal_5fde8c6918ebc.pdfIn PDF document text
    • https://didipovewefof.weebly.com/uploads/1/3/4/3/134306756/betiduripobe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480148/normal_6031abe7d0eb7.pdfIn PDF document text
    • https://xadebunurag.weebly.com/uploads/1/3/1/4/131454816/furowawuxuk.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/c4c907e5-5201-4737-8ace-5eb0a56a1d8f/diono_radian_3r_vs_3rxt.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2e7f77eb-68f7-45b8-a467-b03610a3cea4/musuxudunutefevu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/efdd117c-6f20-4b6e-a868-aa08a4dbbc18/3776665251.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8d33af4-db2b-47c9-96f0-6d06e9e139ac/mouse_guard_roleplaying_game_box_set_2nd_ed.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_off0000ecc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC5 5084 bytes
SHA-256: d038df05d8aafc99428ae374782fc482c7612b46f4b9ada52851eec28ce5618c
font_01_sfnt_off0000fe2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE2E 11012 bytes
SHA-256: 3efea99352fe7b34f6fa101757c8adb9e5334b7f9918b8348cd0cec2aebf1444