Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9b7a5b26edab0d4…

MALICIOUS

PDF

76.1 KB Created: 2021-09-19 13:45:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6383cda8d303d1886bc5283149bef576 SHA-1: cf072942975642936e0e06d79ef6a2084a45a8e4 SHA-256: d9b7a5b26edab0d4bd48ac46646dde4c37ebdb06ae60ddd771a66900f66c7965
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to potentially disposable domains. The ML classifier strongly indicates maliciousness, and the heuristic for a link farm further supports the conclusion that this document is designed to redirect users to malicious sites. The embedded JavaScript likely facilitates the redirection or exploitation process.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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://machi-tomo.xyz/js/ckfinder/userfiles/files/64838125049.pdf In PDF document text
    • https://sukaunited4d.vip/contents/files/ragakatejasu.pdfIn PDF document text
    • https://www.tristar-technology.com/ckfinder/userfiles/files/44907265188.pdfIn PDF document text
    • http://fiorenzuolatrack.it/userfiles/files/9643142752.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/memamijigitit.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/66724931912.pdfIn PDF document text
    • http://madurastones.com/userfiles/file/15418546341.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/lamiburuxokixoxober.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/87358023713.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/rixabe.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613733244da3d---82086077844.pdfIn PDF document text
    • https://icoachyou.biz/images/ckeditor/files/jiwatexakokakuv.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/66022368926.pdfIn PDF document text
    • https://eletroluz-al.com/_IMG/img_internas/file/riviwukadezagenoxo.pdfIn PDF document text
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/44208875141.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021091908274881.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613df7c94fa6f---48269981396.pdfIn PDF document text
    • http://www.synagoge-stommeln.de/ckfinder/userfiles/files/10779696408.pdfIn PDF document text
    • http://levant-tekstil.com/other_files/File/lebozetudexuj.pdfIn PDF document text
    • http://savaksangida.com/resimler/files/1807203337.pdfIn PDF document text
    • http://eshop-kocicinadeje.cz/files/file/26802072408.pdfIn PDF document text
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/32684266574.pdfIn PDF document text
    • https://alirezamirmohammadi.com/images/upload/files/xemipisudijoxibebitalare.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=60+seconds+ios+freePDF link annotation
    • 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_off0000c7ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7FF 16856 bytes
SHA-256: 1544d6cf4c3cf43d332fb4217465175ae9d7bd3eb5cde0b3b05d1acf747b61b6
font_01_sfnt_off0000f39c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF39C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010bb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BB3 10356 bytes
SHA-256: 88907d5f565e28b8993c5890a8cc895396d18b3458ac49df5d78f57335d4639e