Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec8a3da558b7c725…

MALICIOUS

PDF

82.5 KB Created: 2021-09-18 13:28:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b15bd162bdbf223ccd99f86ad96b6619 SHA-1: 1eaa6492267fcca55171c9f723baae252e9f05e1 SHA-256: ec8a3da558b7c7259737bf169a7d6d90df66808a07e1712ad58cf0101447cfbf
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are identified as part of a link farm on disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious content.

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://coretry.ru/uplcv?utm_term=free+skin+ml+apk+2020 PDF link annotation
    • http://noithatachau.vn/webroot/img/files/zobamugirasusamanukexugep.pdfIn PDF document text
    • http://thegioicamdo.com/upload/files/xokobisaresagowarexavuwaz.pdfIn PDF document text
    • https://777mto.info/contents/files/82229608075.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/90939344115.pdfIn PDF document text
    • http://almar-bus.pl/userfiles/file/bumabutunodovatenukubi.pdfIn PDF document text
    • http://ramenhajimetustin.com/uploads/files/savomuvoliwifepamokaxo.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/161316669d9a6a---zifewukulo.pdfIn PDF document text
    • http://eiak.org/upload/editor/files/lewenagegomofo.pdfIn PDF document text
    • https://papiratisk.cz/soubory/winowe.pdfIn PDF document text
    • http://ride-on-earth.com/images/blog/file/xoxusujitajujesudax.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/5811604276.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109131938523749.pdfIn PDF document text
    • http://178.62.148.222:300/ckeditor/ckfinder/userfiles/files/48386323093.pdfPDF link annotation
    • http://murzilka.biz/images/uploads/file/67657899142.pdfIn PDF document text
    • https://eagle-aviation.com/userfiles/files/papizomavomavig.pdfIn PDF document text
    • http://massiimo.com/piceditor/file/25859061014.pdfIn PDF document text
    • http://hydrem.ru/images/file/mejujobexiz.pdfIn PDF document text
    • https://villanakarin.com/userfiles/files/zezuvorisimaru.pdfIn PDF document text
    • http://bjsixiang.com/jingkelun/userfiles/files/20210903224437.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/penizakiloderowam.pdfIn PDF document text
    • http://xedaptheduc.net/app/webroot/uploads/files/nopusogofa.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/dimusigibogedo.pdfIn PDF document text
    • http://shengyaweb.com/uploadfile/file/2021090810141840.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/detupaburup.pdfIn PDF document text
    • http://suphammamnon.org/uploads/files/24168051830.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_off0000e14c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE14C 16812 bytes
SHA-256: 15f7a2a8595716896f5b6064cdeb1c0b26137f8bacd32bf12f1c22d8d3960dba
font_01_sfnt_off00010cfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CFB 10504 bytes
SHA-256: d2c14417c7ebaf60f01d77396be76e897627fada54e899fe57e0021decc30cd7
font_02_sfnt_off000124d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124D7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1