Malicious PDF — malware analysis report

Static analysis result for SHA-256 928ea127ab90a667…

MALICIOUS

PDF

68.5 KB Created: 2021-09-24 13:45:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f5c415a23a00defade8dedfc6848c853 SHA-1: 5b7e11b8796fadbaff4470efb8dad6cdd0fc13e9 SHA-256: 928ea127ab90a667aeecb9e1f85d3a7fef680751becb069b9d6d1e27f8cf1245
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is identified as an image-only document with an action trigger, a common lure for phishing. It redirects to multiple external URLs, many hosted on compromised CMS uploads or disposable domains, suggesting an attempt to lead the user to malicious content or phishing pages. The ML classifier strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

Heuristics 7

  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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.
  • 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 https://pistant.ru/uplcv?utm_term=the+game+of+chess+by+kenneth+sawyer+goodman+essay+in+english
    • http://ndc-group.ru/uploads/files/37573643757.pdf
    • https://badanie-wody.pl/galeria/file/masanimubidixebiva.pdf
    • http://diplomat2014.ru/ckfinder/userfiles/files/bosetadovupinuxodimodeji.pdf
    • http://uniontsg96.ru/admin/ckfinder/userfiles/files/lilifirusitolufexe.pdf
    • http://jlsxjy.com/right/UploadFile/file///2021091413482573499.pdf
    • http://xn--80aaaaadfwa5aftjhxrkcrg8iwc.xn--p1ai/pict/file/33650652613.pdf
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16147ffb5b41b3---15126740522.pdf
    • http://imobilestore.de/userfiles/file/zefidewanogudeloferub.pdf
    • https://landtop.com/filespath/files/20210903000902.pdf
    • http://sunnyten.net/userData/board/file/19511227780.pdf
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/ziduzatadurunajixufena.pdf
    • http://isgsrl.it/images/file/78669895805.pdf
    • http://oilspecchem.com/files/sibifofi.pdf
    • http://agro-pasz.pl/ckfinder/userfiles/files/rexozu.pdf
    • https://aksusu.com/upload/files/36599252654.pdf
    • http://karinameal.com/imgdish/files/22885719127.pdf
    • http://namlinhchivietnam.net/userfiles/image/file/xudedoxododem.pdf
    • http://maraulsan.com/ckfinder/userfiles/files/gexafidilomawemiduzasewot.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/vqk6ufacu77icr7ak2k60c93tk/43793520170.pdf
    • https://suthuytinh.com/app/webroot/uploads/files/2156036024.pdf
    • http://speed-r.com/js/upload/files/razosevexa.pdf
    • https://agrocare.ro/ckfinder/userfiles/files/84119574818.pdf
    • http://supragyn.cz/userfiles/file/88417796918.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/a34f5269d4c547b6831843dc051c8d3c/tabigozebabinefavitedolo.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16140ce5dc218a---donuru.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b012.bin
20961483de263b247c13c000894e8f302a4d3cd6c2e8b4b1d6303e8a8288e161
pdf-font-stream PDF embedded font (sfnt) at offset 0xB012 11320 bytes
font_01_sfnt_off0000ca69.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA69 16792 bytes
font_02_sfnt_off0000e27b.bin
dd0976bb203934684e5d5eee2bf57ca553fe28e7ebd268f9fcf5d49abe37e6d5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE27B 13744 bytes