Malicious PDF — malware analysis report

Static analysis result for SHA-256 3713241704540b31…

MALICIOUS

PDF

76.3 KB Created: 2021-03-13 23:43:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 972cfbffcdfa1dedebbf79e6f1cd9fd2 SHA-1: f9cff5f8dee26d34db0625bde3e255b353d00f21 SHA-256: 3713241704540b3115edbdbebcb54bf6ea4e4a00cfb6db4b5a143542796b4199
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, identified as a link farm, with a primary suspicious URL pointing to 'jottigo.ru'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or SEO abuse. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://jottigo.ru/award?keyword=behavioral+school+of+management+theory+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4468827/normal_603174cc1e69c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4428033/normal_603b775c6a7fc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4403418/normal_5fedf4635ffb3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388041/normal_5fd8e53b0ffd1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://6e3eaeb2-b9dd-4462-8b56-96c59beebd9a.filesusr.com/ugd/dcc11b_d51172de4b3540fe85ace45f39e70ed1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/25ef983a-4a17-431d-b5bc-61a4f7b7ea72/tifamukodoxefireli.pdfIn PDF document text
    • https://s3.amazonaws.com/zebarufuridorur/zasisob.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/065545a6-9054-4d90-9571-c956b50afcc7/67054395810.pdfIn PDF document text
    • https://s3.amazonaws.com/rekorewexidiwo/52754311669.pdfIn PDF document text
    • https://86908e24-11f3-43a1-9346-bf531f45ee0b.filesusr.com/ugd/97493d_de99dd8f88614b42a4e1dbf9799a7930.pdf?index=trueIn PDF document text
    • https://064d663d-f6b2-44cf-a6ad-083da5f315e5.filesusr.com/ugd/77eba6_01c31e81f5e84a9b9aec584844be4204.pdf?index=trueIn PDF document text
    • https://c2dbac7f-2075-4dc1-ad03-af0d0352bff2.filesusr.com/ugd/278743_27a5e9cb9d0d45bcbeee15936bd1dd63.pdf?index=trueIn PDF document text
    • https://c36efdde-2309-4ce2-a10d-b6df2ce12cd8.filesusr.com/ugd/e98059_97f6e26069d44ec58772e9cfdf5d1c3b.pdf?index=trueIn PDF document text
    • https://fd0ef26f-7b8f-4c91-b3b2-19f7ec93487a.filesusr.com/ugd/4174bf_58c25f05e7e0481e9c43535fac0a0bc3.pdf?index=trueIn PDF document text
    • https://2ea9429b-0332-4ee6-bb75-ab9535b56c99.filesusr.com/ugd/e2f7e1_ca5dabff1eb248beab7267c087f018fa.pdf?index=trueIn PDF document text
    • https://db6a684c-bd73-4a61-997a-17040cc1d896.filesusr.com/ugd/bbbb20_3b8ce76af3dc46f590ad962e3fda48ac.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wakuzidi/ruxifozojoroxutoru.pdfIn PDF document text
    • https://0ccb9a81-bd3c-41bd-bc79-2352350f0e5e.filesusr.com/ugd/95ea6b_de6e49ca8dc140c38edfc629a8cf5375.pdf?index=trueIn PDF document text
    • https://a24bc4ef-4ee2-4fae-af0c-c9fea810b245.filesusr.com/ugd/67d96c_7a1f3657f79943d49f1cce96b955538e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/884ba3a9-c651-4a74-aa20-fab1b612c426/materia_relacion_con_la_energia.pdfIn PDF document text
    • https://7f1d4f38-7308-4051-b389-b8ed31312188.filesusr.com/ugd/e948c1_549b084fe11b41549ededbb46783055a.pdf?index=trueIn PDF document text
    • https://eee5dff6-7331-416e-acdf-593d0c386862.filesusr.com/ugd/21e9e0_f1d39753c0f34fab958cade11ca63131.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE9A 5780 bytes
SHA-256: 05c301b23b0f5861f8c54c54d39599c4918539f13860cf09853dc7b1587864c6
font_01_sfnt_off0001022d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1022D 10660 bytes
SHA-256: 583affe1e2a859eef7950064f4243acd3f9e638dbc31ef3663d3d9a5f663a7bb