Malicious PDF — malware analysis report

Static analysis result for SHA-256 b998b8cbbfa6bd4d…

MALICIOUS

PDF

70.3 KB Created: 2021-09-21 08:11:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a5edab0e79429d3b2f70f99223a65432 SHA-1: 91abdcd1611426ec0350e65702759a8b5be9cb2f SHA-256: b998b8cbbfa6bd4d24e8313c53fd2c7e22bfc0c249d14d050d529dc57058d5a1
134 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs that redirect to other PDF files, indicating a link farm designed to host malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the structure and numerous external links point towards a malicious workflow.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://catamma.ru/uplcv?utm_term=a+quiet+place+2+full+movie+tamil+dubbed PDF link annotation
    • http://udelimpa.es/ckfinder/userfiles/files/zafafibo.pdfIn PDF document text
    • http://wignaccent.com/FCKeditor_2.6.3/userimages/file/20210917162422.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name/files/17066074513.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613db15448753---99862602837.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/82890744762.pdfIn PDF document text
    • https://aordonez.com/images/contenidos/files/gizikodonikevererilepop.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/61109281882.pdfIn PDF document text
    • https://tkquiz.com/userfiles/file/wuzeke.pdfIn PDF document text
    • http://studiorestagno.eu/userfiles/files/77933260007.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/wumumurigojoxakudevub.pdfIn PDF document text
    • https://ecohort.biz/userfiles/files/96912826947.pdfIn PDF document text
    • http://tandartsindex.nl/images/uploads/94616535652.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/viwofinapo.pdfIn PDF document text
    • http://soc-in.com/data/media/files/38499897398.pdfIn PDF document text
    • http://omni-links.com/images/blog/file/lenabulizagapep.pdfIn PDF document text
    • http://shinyoungvalve.com/userData/board/file/komoxinanowisobamaxin.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/fotovatukugiru.pdfIn PDF document text
    • http://razzledazzleevents.in/userfiles/file/ligijixubutazokadibov.pdfIn PDF document text
    • https://umiyawoodworks.com/fckdb/userfiles/file/tawazumamagabaja.pdfIn PDF document text
    • http://floramarble.com/uploads/97028251605.pdfIn PDF document text
    • http://plaschke-partner.com/uploaded/file/femerosobesu.pdfIn PDF document text
    • https://ncltandatbar.com/home/ncltandat/public_html/dowalumniusa/ckfinder/userfiles/files/23922208626.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/161413a0203d6b---72142517905.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/88429050021.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b14a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB14A 10960 bytes
SHA-256: e55fdca766a9f261b98febb3c669477bc65ac57475f9a2a49adb3edc3216661c
font_01_sfnt_off0000ca66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA66 16088 bytes
SHA-256: 4966235fa4aedd3b973b12ff274cb9f379b9efaf00220acfad4d4eb8e1dc4055
font_02_sfnt_off0000f3d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1