Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf488185844abc1e…

MALICIOUS

PDF

78.1 KB Created: 2021-06-08 00:48:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 183a0e4c1c7c85d523ccb6961cbddafd SHA-1: b18eb03c1b09d8124d6fa00923b5bd7d29f0f819 SHA-256: cf488185844abc1efe2cca9b67b3e1eaaac4b6ba3ac6d90f37c6ec0dde0e8ea7
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 0.9955

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/123?utm_term=answer+machine+for+samsung+mobile PDF link annotation
    • https://sosabugipos.weebly.com/uploads/1/3/4/6/134657522/vexabuva_nonumi_salomi_fiwipepidabitat.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471275/normal_60249cf2dc5a2.pdfIn PDF document text
    • https://zogoporev.weebly.com/uploads/1/3/1/3/131381602/vibotebofazafob.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4368228/normal_60b04882af70d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4389352/normal_5fe556bcd46d3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369932/normal_6044c9ad47c76.pdfIn PDF document text
    • https://lewixixidofuj.weebly.com/uploads/1/3/4/3/134393564/remazot.pdfIn PDF document text
    • https://zozolesib.weebly.com/uploads/1/3/4/6/134631165/7116835.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407996/normal_604162c9b1cf7.pdfIn PDF document text
    • https://romitigab.weebly.com/uploads/1/3/4/8/134864794/565bc0f8184aa48.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450242/normal_60357da9d5ac6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376856/normal_605c3930deee6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450355/normal_602599c2f10db.pdfIn PDF document text
    • https://xixotileko.weebly.com/uploads/1/3/4/0/134018517/7002186.pdfIn PDF document text
    • https://fefosixofenovi.weebly.com/uploads/1/3/4/7/134755919/8203927.pdfIn PDF document text
    • https://xojerajap.weebly.com/uploads/1/3/1/3/131384359/1425580.pdfIn PDF document text
    • https://rukeruxesam.weebly.com/uploads/1/3/4/7/134700508/jozajig.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/55d35897-c57a-4a6a-82d5-60aead385295/could_not_connect_to_netflix_code_ui-113.pdfIn PDF document text
    • http://sagidetubi.pbworks.com/f/vokej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fe059be6-8fcc-42ab-86b6-76b51784b7e7/netedunenireduma.pdfIn PDF document text
    • http://vazesuna.pbworks.com/w/file/fetch/144519489/xofebubexirubibipafefo.pdfIn PDF document text
    • http://nawujewo.pbworks.com/w/file/fetch/144690357/16875159817.pdfIn PDF document text
    • http://foxobekizax.pbworks.com/w/file/fetch/144464565/uur_mumcu_nun_krt_dosyas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa67e921-ab76-4ef4-ace3-bb81a3e3dc6d/walking_dead_book_in_order.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd11ae91-9ec3-41ac-9995-a14562110bc6/nirobadares.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8eed15c3-9d3d-402b-a46e-d4b670c156ab/yo_amo_a_juan_querendon_capitulo_1_online.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_off0000f1fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1FA 5516 bytes
SHA-256: a4aae8538069d85d135fa215b3442c447adb08f4f352cf285bb38ae2f6d6b943
font_01_sfnt_off000104a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A3 10996 bytes
SHA-256: ca03203cf91a8a154d315eae5fb00ab2b094e443c0d94c44a4b1f8523cfe58b1