Malicious PDF — malware analysis report

Static analysis result for SHA-256 f809c49081263495…

MALICIOUS

PDF

79.2 KB Created: 2021-03-20 00:56:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 680f999556c176a32e4c612724300632 SHA-1: a5e7e1d15b5eea7cc1bf7649ee9d8a8c1bd15eac SHA-256: f809c490812634955ce6324ff16bc12d1a52ce256e3ed03bf954dd0f8d2fc4cf
252 Risk Score

Malware Insights

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

This PDF file contains a large number of embedded links, many pointing to disposable domains, suggesting a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to phishing sites or distribute further malware. The presence of a 'download button' lure reinforces the deceptive nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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.
  • 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.
  • 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://dafemum.ru/award?keyword=ncert+sociology+class+12+part+2+pdf In PDF document text
    • https://cdn.sqhk.co/gepeduvo/igyjjgg/zepagopin.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368956/normal_601363ca4eae1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470552/normal_6014165d6bd51.pdfIn PDF document text
    • https://nowiwadigomu.weebly.com/uploads/1/3/4/0/134018048/7279133.pdfIn PDF document text
    • https://cdn.sqhk.co/gixelotopa/jiahcqH/23634439995.pdfIn PDF document text
    • https://webexozaputer.weebly.com/uploads/1/3/2/6/132681415/fotusugok.pdfIn PDF document text
    • https://loxoxonejuk.weebly.com/uploads/1/3/4/6/134684666/gitalejifaxemumup.pdfIn PDF document text
    • https://cdn.sqhk.co/vewukiziwemi/gkW4tha/fowukofikomigofoxidavejit.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403413/normal_5feb19cc2f37b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500425/normal_5fc572921c135.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8dfdba76-182f-4dc4-9dda-37a8c8d09dc9.filesusr.com/ugd/4ae4db_de1f0c60c5d84b259df97790f8f77838.pdf?index=trueIn PDF document text
    • https://c18d7360-3707-4bf1-9d6f-52ba7510fa17.filesusr.com/ugd/76cb06_a17f239942e4427d99a8cde652e877dc.pdf?index=trueIn PDF document text
    • https://fec450ea-b80f-4746-b851-35139cc02de5.filesusr.com/ugd/53a83b_08fef516338f4eaf955506ad74e4d5c5.pdf?index=trueIn PDF document text
    • https://c6f55193-7475-4343-97dd-33cb3b141b6a.filesusr.com/ugd/808d8c_9810e3d6405e41d3bcc69aaf088eb6a6.pdf?index=trueIn PDF document text
    • https://eb40363d-1d1f-4170-a897-f23f0f433116.filesusr.com/ugd/2a1429_09982edc9e8b4bcbad121004154bf626.pdf?index=trueIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_36f7de94d229488db3a538259e86743f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tawovojo/calculus_1_and_2_cheat_sheet.pdfIn PDF document text
    • https://fec450ea-b80f-4746-b851-35139cc02de5.filesusr.com/ugd/53a83b_734c0e84e0204bf085f9c58607ed8ec1.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zamuriza/ascii_format_characters.pdfIn PDF document text
    • https://03ca3561-abfe-48ca-9b59-b1b2b77f8126.filesusr.com/ugd/1af49e_02d8b1451f24490d83cc7df70067bc28.pdf?index=trueIn PDF document text
    • https://cf2e1f24-e5f1-4289-9567-3affce9c164e.filesusr.com/ugd/a4ea6c_f16877e43d1646c4b9b888ce677a5721.pdf?index=trueIn PDF document text
    • https://9e269ae7-c3cf-4b9f-bde2-1d9be064b7bf.filesusr.com/ugd/139869_ac6cb2a2fe3d4552bf3afc43c52fc5c3.pdf?index=trueIn 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_off0000f772.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF772 5580 bytes
SHA-256: 02bf9be01bc8508abbfaff8aa7f6a43a36385eb04885ec5638cfa1e5f183bdb6
font_01_sfnt_off00010a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A98 10800 bytes
SHA-256: 72f765ecfb722abf6452b9ec5379428a25b369579b2580ea6755ca8a1810f425