Malicious PDF — malware analysis report

Static analysis result for SHA-256 e91ddcbdc11f94cf…

MALICIOUS

PDF

81.9 KB Created: 2021-04-06 22:43:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: d5335816ee99d21e2f1115e5c6a45c26 SHA-1: 4be2dd7de8de2e82aa384a5a42e6e13f9b29506e SHA-256: e91ddcbdc11f94cf35131f857c80c03cc36f67321d02487aca86fd1e80d97b76
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam campaign. The ML classifier and ClamAV detection strongly indicate maliciousness, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and extensive external linking are indicative of malicious intent, possibly to redirect users to exploit kits or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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://vilenefex.ru/strik?utm_term=learn+r+programming+for+beginners PDF link annotation
    • https://wipabobape.weebly.com/uploads/1/3/5/9/135985954/6846200.pdfIn PDF document text
    • https://xopilujipuwoka.weebly.com/uploads/1/3/4/8/134886601/3525daa6fd99abb.pdfIn PDF document text
    • https://jolejijiwunepa.weebly.com/uploads/1/3/5/3/135334118/damagalinosamifa.pdfIn PDF document text
    • https://wiruwopifezub.weebly.com/uploads/1/3/4/3/134345133/rirelek.pdfIn PDF document text
    • https://tuwunofibe.weebly.com/uploads/1/3/4/6/134657164/7390f1ac.pdfIn PDF document text
    • http://marafonsport.site/applied_linguistics_journalzohon.pdfIn PDF document text
    • https://lufosafol.weebly.com/uploads/1/3/0/7/130775677/2926019.pdfIn PDF document text
    • http://fijexojor.getenjoyment.net/tuvuvowufixugixosamirite.pdfIn PDF document text
    • https://jasefeneg.weebly.com/uploads/1/3/4/4/134489721/gijidim_rusewuzab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475999/normal_601d67a6464ad.pdfIn PDF document text
    • http://healsmall.space/representative_payee_online_formcfy8c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459326/normal_5ffb62e93f2ee.pdfIn PDF document text
    • http://wirobigi.medianewsonline.com/accept_vs_except_worksheet.pdfIn PDF document text
    • http://on24-system.club/google_chrome_for_android_5._0_apkpg10i.pdfIn PDF document text
    • https://winomawapaba.weebly.com/uploads/1/3/5/3/135334931/6906486.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423714/normal_601ca922f0f30.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/c9814276-6977-459b-9a3a-a588c30260a7/dizofidaferav.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6a3f6d94-da95-4559-92ce-b423ad10c132/dolira.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/507c1e6c-bd22-47e7-999c-4798ca85412c/67650411608.pdfIn PDF document text
    • http://jeximojela.myartsonline.com/99247023069.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6239bb5-1b14-4920-8856-a7255b844866/lalipunimofabegatomep.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/813b3005-3a7c-4bd9-9bb7-aacf2ee469cc/why_does_my_dryer_drum_not_turn.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_off000101a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A3 5272 bytes
SHA-256: dc789c1779e3f80d7a430531d0bca94f98f162ef484382a0c29624dad3444708
font_01_sfnt_off00011382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11382 11348 bytes
SHA-256: f564f623fce88d576e6dd461acaa52a8e2a48c3d4a2b0dadabbe0a9acb6132a7