Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c239bd7275e72fc…

MALICIOUS

PDF

73.8 KB Created: 2021-03-24 16:13:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 3c7baeb0705241eafeb08e9c0f1c1f3e SHA-1: 2a0c67c96a43f6bc147a2be1d5329f7d9a12fe68 SHA-256: 0c239bd7275e72fc4dd75e5db870ee107d2dba9aa21452da88af4804a35edeba
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs that point to other PDF documents, likely to manipulate search engine results or host further malicious content. The primary URL observed is https://jottigo.ru/123?utm_term=simile+or+metaphor+worksheet+pdf, which is part of a disposable link farm strategy.

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://jottigo.ru/123?utm_term=simile+or+metaphor+worksheet+pdf PDF link annotation
    • https://cdn.sqhk.co/zarejesorufo/U50DjaP/agnisakshi_serial_full_audio_song.pdfIn PDF document text
    • http://tafuxasomup.getenjoyment.net/7267769810.pdfIn PDF document text
    • https://cdn.sqhk.co/turaxulefa/fifRgjc/88315139177.pdfIn PDF document text
    • https://cdn.sqhk.co/bomemenun/ShfLYDt/41273681073.pdfIn PDF document text
    • https://cdn.sqhk.co/davunosedepa/hj9hcne/survival_craft_2_minecraft_texture_pack.pdfIn PDF document text
    • https://cdn.sqhk.co/nivavepe/aMgc86a/55567150043.pdfIn PDF document text
    • https://cdn.sqhk.co/kepebeso/hde7U4D/bagiforenasovuxazajerizo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1d942ef5-affb-47d8-8f99-70a3d187b733.filesusr.com/ugd/3283b0_2233bf707b3549d9b6c9ad9ae25d949a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dexodekelaseki/gemorawipiboge.pdfIn PDF document text
    • https://e510c2d5-567e-4a96-89ff-abc18316baf7.filesusr.com/ugd/8a9bcc_82353779cb124f5ca3e5cf488559bce6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f90d685b-1ae5-45dd-80b3-24f26c5fcd0d/administracion_de_medicamentos_por_via_intravenosa_directa.pdfIn PDF document text
    • https://s3.amazonaws.com/zakunafu/pulozesuxes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/91e3eb7f-3338-4664-aff8-f25307dd1e51/60405984105.pdfIn PDF document text
    • https://s3.amazonaws.com/lanaladu/xojegalegot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1a77710-fac5-405c-82ca-3a5eb520c478/pretty_little_liars_episodes_season_4.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/335d9aca-57ca-4dc2-a8ab-6ae765a49ee2/brandy_melville_discount_code.pdfIn PDF document text
    • http://metiguwuwezaza.atwebpages.com/study_of_boilers_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/00c74240-9898-48b2-ac77-efe7d4c74adf/laporin.pdfIn PDF document text
    • https://4ef57e19-9a2e-4e6f-a444-f6b59f982a39.filesusr.com/ugd/4c1554_24df2da7e16d40dfbf8bf94d90b1fa4f.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tumuzu/rowdy_baby_video_song_3gp_free.pdfIn PDF document text
    • http://sofibimibojas.myartsonline.com/varudulowejava.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_off0000e1b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B3 5540 bytes
SHA-256: 44d26b22af0a340685c8e5bcbc057de35ad64e7a45230dd4dde72a42978ae6dd
font_01_sfnt_off0000f46a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF46A 10988 bytes
SHA-256: 751f752f162df4da88b8183629f94cb1974ab009205cfa5f2d1b7b0306c281e6