Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5ad5fd3655e3737…

MALICIOUS

PDF

89.1 KB Created: 2021-09-20 06:21:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b2fae9b2a88a0683413649f26c33cb2e SHA-1: 668489b6520736e7935108b72b41e5a97fe6b1ee SHA-256: a5ad5fd3655e37372f176993cf3dd72ebb78e15fe4cf087bd66a7d5f304c578a
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs pointing to various domains, suggesting a link farm or redirection scheme. The ML classifier strongly indicated maliciousness, and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirms the suspicious nature of these links. While no scripts were directly extracted, the structure and embedded URLs are indicative of a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 4

  • 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://infrive.ru/uplcv?utm_term=traffic+rider+game+download PDF link annotation
    • http://levotst.com/uploads/files/ropisilil.pdfIn PDF document text
    • http://mikomisushi.com/uploads/files/mawonofosewewelu.pdfIn PDF document text
    • https://noursportevents.com/wheelmarine/userfiles/file/31489128711.pdfIn PDF document text
    • http://grandviewgroupresort.com/upload/files/bofafuturugolasopun.pdfIn PDF document text
    • http://astorandblack.net/emailer/userfiles/file/dokulaxugofetedojivi.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/48146138176.pdfIn PDF document text
    • http://aallergy.friend-match.com/upload/files/65604728231.pdfIn PDF document text
    • https://www.lipca.com/ckfinder/userfiles/files/71218889380.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/pikozeda.pdfIn PDF document text
    • https://harmony.im/userfiles/file/5931201625.pdfIn PDF document text
    • http://descanso.verareyes.com/ckfinder/userfiles/files/tanomeru.pdfIn PDF document text
    • http://hyundainhapkhau.net/upload/files/56271247200.pdfIn PDF document text
    • http://mis.nrru.ac.th/gradjournal/ckfinder/userfiles/files/40015348840.pdfIn PDF document text
    • http://youzedu.com/ckimages/files/20210915152545512234.pdfIn PDF document text
    • http://powercleanperu.com/cms_powerclean_2015/sgi_userfiles/userfiles/files/40754470723.pdfIn PDF document text
    • http://www.monts.sk/upload_images/file/muxisofakajinoxu.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/voboredaw.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/2qbieapqleg8su64q5abv95te2/wujeviluxame.pdfIn PDF document text
    • http://besteva.com/upload/files/tenagipogir.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/36963441492.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/161320bf27a988---5179362515.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD509 10604 bytes
SHA-256: 58b79ce0cbd13648768035ad312575e0e8757f4bd1626c272b5573c4824934b7
font_01_sfnt_off0000ed16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED16 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10528 23484 bytes
SHA-256: ff05e8f3e46f80ec6a2631fc3d95ca8b1bdff2ff840eaccf709fff994b435ff4
font_03_sfnt_off00014108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14108 16104 bytes
SHA-256: 4204f4a647e3e8488fc3125e36d68471fcc515b787f7ef36a685bb1e406e82a7