Malicious PDF — malware analysis report

Static analysis result for SHA-256 25273bc41504b2fc…

MALICIOUS

PDF

80.2 KB Created: 2021-05-29 11:58:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cbb05742ff45fb2f4e528f414442d537 SHA-1: c80a02e005ae75ab09b678e3b9d0139fbe51fcbe SHA-256: 25273bc41504b2fcace3482d4a584b16b29ec8946f71301b21519041299481f5
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF document identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many of which are likely part of a link farm, and the document body suggests an advance-fee scam lure. The primary URL, https://resalured.ru/strik, is likely the entry point for this malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Advance-fee lottery/parcel scam lure high SE_ADVANCE_FEE_SCAM_LURE
    Document contains lottery/beneficiary or prize language together with large-value draft/funds wording and parcel/courier delivery requirements. This is a classic advance-fee fraud document shape.
  • 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://resalured.ru/strik?utm_term=toastmasters+meeting+themes+2021
    • https://cdn-cms.f-static.net/uploads/4403948/normal_601aefd3d3311.pdf
    • https://cdn-cms.f-static.net/uploads/4487382/normal_5fd85c18cfde9.pdf
    • https://lozoveku.weebly.com/uploads/1/3/1/4/131438804/a80c8.pdf
    • https://kowedogade.weebly.com/uploads/1/3/4/8/134879104/6120d9.pdf
    • https://wasafigazepez.weebly.com/uploads/1/3/4/5/134586721/5500039.pdf
    • https://dumexegutotopu.weebly.com/uploads/1/3/4/3/134354144/ritat.pdf
    • https://cdn-cms.f-static.net/uploads/4411483/normal_601b2f7551e26.pdf
    • https://dituwugo.weebly.com/uploads/1/3/4/2/134235792/4358861.pdf
    • https://guzesunidami.weebly.com/uploads/1/3/0/8/130873942/6574512.pdf
    • https://cdn-cms.f-static.net/uploads/4380863/normal_5fd99706b4f05.pdf
    • https://cdn-cms.f-static.net/uploads/4375518/normal_6040c2b88cc57.pdf
    • https://vumopiwerelo.weebly.com/uploads/1/3/4/7/134730258/muginawaluxuna.pdf
    • https://static.s123-cdn-static.com/uploads/4412573/normal_5fcfb300f054c.pdf
    • https://static.s123-cdn-static.com/uploads/4457272/normal_60027a0b8b2c7.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/9be0135e-3765-46f8-8be5-5cd85d0d5a16/how_to_be_the_perfect_1950s_housewife.pdf
    • https://uploads.strikinglycdn.com/files/6fdcbc59-dea3-4172-a1aa-7e1de27f4b69/kesusaluwa.pdf
    • https://uploads.strikinglycdn.com/files/471ae7f4-af95-4ec7-ac62-29201807df92/23247292816.pdf
    • https://uploads.strikinglycdn.com/files/f52b4c38-d2fb-4949-a1f2-ca001fbbd551/repevibiwigadenagiwuro.pdf
    • https://uploads.strikinglycdn.com/files/ef2e6d38-b676-432b-89fa-e6b29b8f648a/wobeniwogimijojun.pdf
    • https://uploads.strikinglycdn.com/files/81190882-77d5-4ed2-bc5b-2b543c88b3e6/kabir_singh_all_ringtone_download_mr_jatt.pdf
    • https://uploads.strikinglycdn.com/files/5286191e-6922-40a1-90c5-17c64df3642f/tidusa.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed14.bin
a738fbdacbb1d023503d6efbe3d9e48873d287ad45cd692d8bf8b4ca2a2fe14a
pdf-font-stream PDF embedded font (sfnt) at offset 0xED14 5128 bytes
font_01_sfnt_off0000fe52.bin
7327027f2d6629c59dba678eef187f49ca798e8807d41974b7699a7ec617e9b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE52 11724 bytes
font_02_sfnt_off0001254c.bin
d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
pdf-font-stream PDF embedded font (sfnt) at offset 0x1254C 4324 bytes