Malicious PDF — malware analysis report

Static analysis result for SHA-256 1987bc5cee0c6889…

MALICIOUS

PDF

83.2 KB Created: 2021-05-24 04:41:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 3add8ba5d37c19f95e4cdea275903b0c SHA-1: 1ec9a2c26e11bee8139a67c021f07a1be648188c SHA-256: 1987bc5cee0c6889f0829b420b0b04027a377cbc77815fe2dd8edb22a47d3710
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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://nipisod.ru/strik?utm_term=what+instrument+is+used+to+measure+air+flow PDF link annotation
    • https://senuwisaf.weebly.com/uploads/1/3/4/0/134018119/tebeno.pdfIn PDF document text
    • https://zezojafoxivofed.weebly.com/uploads/1/3/4/5/134528913/3ce6392.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450418/normal_5fe545f4b5ccb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366958/normal_6035ec69b0949.pdfIn PDF document text
    • https://midezotadodagof.weebly.com/uploads/1/3/5/3/135326840/towimaxexuvir.pdfIn PDF document text
    • https://wavarojejepifog.weebly.com/uploads/1/3/4/5/134590929/pijepuwatini-nuzenudaruna-pebovafikis.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369664/normal_5ff586f6c9bdb.pdfIn PDF document text
    • https://wisolowiguwo.weebly.com/uploads/1/3/4/6/134630140/3032842.pdfIn PDF document text
    • https://dodanopo.weebly.com/uploads/1/3/1/4/131408738/965c267.pdfIn PDF document text
    • https://vamowupa.weebly.com/uploads/1/3/4/4/134435661/sexexopitofofopase.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383566/normal_5feaf3249e16b.pdfIn PDF document text
    • https://panonalosisewe.weebly.com/uploads/1/3/5/3/135316392/degupixetifot-kijajorunepe-fovilapadimexi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472200/normal_6047439086061.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481836/normal_60480befd9b44.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411717/normal_6056b0373ebfc.pdfIn PDF document text
    • https://sipusojatavajuw.weebly.com/uploads/1/3/4/6/134606658/2097626.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4402718/normal_6001453b86ca1.pdfIn PDF document text
    • https://butusokusumowa.weebly.com/uploads/1/3/5/2/135294155/goposelew.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489988/normal_601267e5eba9f.pdfIn PDF document text
    • https://tenanetudoji.weebly.com/uploads/1/3/4/2/134266315/109559.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4496828/normal_606d3d63afc0c.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
    • 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_off0000f9f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F5 5136 bytes
SHA-256: 3f85f18c61a4a3e6d5ad4b1de94d3e07010609f5638bd588d6b1a4cdc4edfa93
font_01_sfnt_off00010b4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B4F 11172 bytes
SHA-256: 33801a39c75bb1d565991e45578f412d5a54f2b64cfb7b349fd56d056d065050
font_02_sfnt_off0001315e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1315E 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2