Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab745b2a78bf4454…

MALICIOUS

PDF

86.3 KB Created: 2021-09-09 22:38:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4bdffcc31b15a878622540bcf17331b8 SHA-1: 4906fdcace6dcbaffd7e2c19165786aee47048bd SHA-256: ab745b2a78bf4454ca22b6777b9e1cac5c26f6a9e514814c2d2eff85b21dc011
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is a link farm designed to redirect users to potentially harmful content. No scripts were extracted from this sample, but the extensive use of external links is a common tactic for phishing and malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://medvor.ru/uplcv?utm_term=tabview+android+example PDF link annotation
    • https://laps.pl/userfiles/file/49299433050.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16136c9ecc95e6---zogivurikasijeba.pdfIn PDF document text
    • http://el-master.ru/userfiles/file/sexokamifitotedajer.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-9-9/20210909172226402120.pdfIn PDF document text
    • http://bociany.sk/media/file/lufubabunarukakunatoxo.pdfIn PDF document text
    • https://lolakarimova.uz/ckfinder/userfiles/files/14276745901.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/wavasetiwamoliz.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338e03d118c---15016115785.pdfIn PDF document text
    • http://thcsducthang.pgdbactuliem.edu.vn/ckfinder/userfiles/files/49473963352.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133b15529467---19698110185.pdfIn PDF document text
    • http://www.cavice.fi/tiedostot/files/58999906127.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/dogesa.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210908120651_1059896328.pdfIn PDF document text
    • https://vhcvietnam.vn/ckeditor/images/files/37321541870.pdfIn PDF document text
    • https://tommytest.dish1314.com/data/html_editor/files/46496700549.pdfIn PDF document text
    • http://vicc.huh.hu/UserFiles/File/xotovijazutozu.pdfIn PDF document text
    • http://mizuho-co.net/file/ck/files/54520365839.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/pizatekedizezefarerezu.pdfIn PDF document text
    • https://pingthye.com/userfiles/files/fomavovijavutudofalabu.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/5399787027.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/55413852868.pdfIn PDF document text
    • https://cian.hr/userfiles/file/tetulen.pdfIn PDF document text
    • https://robindayne.com/ckfinder/userfiles/files/20753163168.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_off0000eba8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA8 10644 bytes
SHA-256: 44a0d623ba4f3e9b50b09e665c703e340e465424b170d8a7fb01ed2158fe0608
font_01_sfnt_off000103cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BDE 18324 bytes
SHA-256: 0ea06f4410f6cedb501a353de6fb9dc718c1b5e864ff22025f88d3870dbe7a25