Malicious PDF — malware analysis report

Static analysis result for SHA-256 73217de30807581f…

MALICIOUS

PDF

79.5 KB Created: 2021-09-10 07:43:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8e1ca5c451d343d50d79c1d96b54efcc SHA-1: 7d4c710b2d14911b78ee959803a5662d905d7512 SHA-256: 73217de30807581f9dd42201abb1db5447cd80822bc6dd3ca97ebc844fb5c1fc
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple links to external PDF files, some of which are hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or initiating further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://abdon.madteam.net/ckfinder/userfiles/files/dinatekib.pdf In PDF document text
    • https://mosaicopeoplecorporation.com/ckfinder/userfiles/files/50618327337.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/29685505246.pdfIn PDF document text
    • http://slenderclub.cz/ckfinder/userfiles/files/sirobomakabowudavenelil.pdfIn PDF document text
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/44507475851.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/mutunikokor.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/93970627607.pdfIn PDF document text
    • http://vnndt.com/Images_upload/files/rabonex.pdfIn PDF document text
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/wazezujevegu.pdfIn PDF document text
    • https://8cj2aja7-8mxb.com/contents/files/vitet.pdfIn PDF document text
    • http://bienbao.org/uploads/files/mewesupemenebazitizogib.pdfIn PDF document text
    • http://teplospectr.ru/images/files/9191275875.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/duxasurijev.pdfIn PDF document text
    • http://clinicaveterinariacittadivignola.com/userfiles/files/votoxajavafaponu.pdfIn PDF document text
    • http://bunny888.com/ckfinder/userfiles/files/64315488996.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/pimugiwemukojapesaw.pdfIn PDF document text
    • http://grasslandtj.com/upload/files/75739622040.pdfIn PDF document text
    • http://zoo-foto.cz/userfiles/file/7309050733.pdfIn PDF document text
    • http://leasingtowers.com/ckfinder/userfiles/files/rafaxod.pdfIn PDF document text
    • http://electronicaindex.nl/images/uploads/43611840569.pdfIn PDF document text
    • http://alles-vom-schreiner.de/userfiles/file/44798233289.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/41968010599.pdfIn PDF document text
    • http://opuspointpartners.com/ckfinder/userfiles/files/zorugajugumejo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+transfer+photos+from+my+old+phonePDF link annotation
    • http://louisiana-arts.org.s150269.gridserver.com/siteuploads/editorimg/file/torolowoke.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_off0000d10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD10A 18024 bytes
SHA-256: 2374e6d3fe38c08ce8ad023e736950281f1f4f309297371a1c4150983536cbaa
font_01_sfnt_off0000ff3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF3B 10864 bytes
SHA-256: 3f1168cd10fb070e25b84602f30f42659ff2b2266a196277cde8b8dc22ee7854
font_02_sfnt_off0001182c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1182C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1