Malicious PDF — malware analysis report

Static analysis result for SHA-256 cee5ba193711b569…

MALICIOUS

PDF

80.5 KB Created: 2021-05-25 05:07:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 155ba74abbf7368658b7d887d1d21520 SHA-1: e3c2f7dfbc6c62ddc7d7a92e913393e85b25fe82 SHA-256: cee5ba193711b569cb396e0d4b2998de28b1a6e2844531e91272976b9c2ba362
126 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many hosted on disposable domains, which is indicative of a link farm designed to drive traffic. The embedded URL `https://nipisod.ru/strik?utm_term=download+bluestacks+3+for+windows+7+32+bit+offline+installer` suggests a lure for software downloads, likely to distribute malware or unwanted applications. The ML classifier strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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://nipisod.ru/strik?utm_term=download+bluestacks+3+for+windows+7+32+bit+offline+installer PDF link annotation
    • https://bonesinidojesu.weebly.com/uploads/1/3/4/5/134591006/4501229.pdfIn PDF document text
    • https://xixipafo.weebly.com/uploads/1/3/4/7/134745113/d25e616b85193.pdfIn PDF document text
    • https://kilukawat.weebly.com/uploads/1/3/4/0/134017116/2d5388.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424996/normal_5fc63979c88e6.pdfIn PDF document text
    • https://pezibufanijazox.weebly.com/uploads/1/3/4/6/134639202/7ba98a9aadad.pdfIn PDF document text
    • https://rurujopolobadez.weebly.com/uploads/1/3/4/4/134444805/wosojeme.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420224/normal_604cf5d33853e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407562/normal_603fff28a4327.pdfIn PDF document text
    • https://dotubebiwujodej.weebly.com/uploads/1/3/4/7/134701593/3bcccb0216f0231.pdfIn PDF document text
    • https://xirofepomare.weebly.com/uploads/1/3/0/8/130814083/4037313.pdfIn PDF document text
    • https://nisudine.weebly.com/uploads/1/3/1/4/131454656/9732249.pdfIn PDF document text
    • https://zobagitolofoxaz.weebly.com/uploads/1/3/0/7/130739917/mifupuwiv_rudetowate.pdfIn PDF document text
    • https://nipituwosaxow.weebly.com/uploads/1/3/5/3/135312928/c2530ddee22.pdfIn PDF document text
    • https://defasoxajex.weebly.com/uploads/1/3/1/4/131405962/boxulot.pdfIn PDF document text
    • https://wawanuxofidote.weebly.com/uploads/1/3/0/7/130775818/ruvujazujuwe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/50898a2e-9c25-461f-ab59-94471c4b5cab/86326520054.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/39837439-fae6-44be-8874-052e0c613454/2005_acura_tl_maintenance_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c3eed27-d638-477c-8ff6-863f2157d564/this_is_the_end_cast_trailer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9a0af263-4aac-468c-92ae-c62af8244fd3/is_the_florida_drivers_test_hard.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da0752ad-c421-459a-8ddb-f95d7a6b066c/2019_can_am_outlander_570_max_service_manual.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEC 5568 bytes
SHA-256: b8a6b5853e795576172d071dc6a7ac7bdf1ccd7ab2c3e3955f3245a83456df2c
font_01_sfnt_off00010005.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10005 11112 bytes
SHA-256: a23c58d1afbf793448b1c8f857048b0f523b2db9a3c331a1c4979eb473148685
font_02_sfnt_off000125e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125E3 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f