Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5a823df5dab726f…

MALICIOUS

PDF

81.1 KB Created: 2021-08-18 19:04:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b0c626d2d23158a801ba2c9a7cad8aa7 SHA-1: 3ec3910af9b624c67c38ccf95b8f56eb4260c782 SHA-256: d5a823df5dab726f442c6420ac80ca7adf326dc168ea8c7e91bb7d8bcae6097e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript and link farm structure suggest the document is designed to redirect users to malicious sites or download further payloads, aligning with phishing and malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=actividades+con+mayusculas+y+minusculas
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e3de196b08.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608a3dad48a7a---fofuwenil.pdf
    • https://decoveinvestment.com/userfiles/file/forulifalor.pdf
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/7onjmqmddkoism9oimr7gqslsr/gefodaveloviba.pdf
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/814b4939fb05164a467513a05c94b766/21185623037.pdf
    • http://edumedcare.pl/upload/files/sokanadu.pdf
    • https://alshaabcoop.com/userfiles/file/bisugimu.pdf
    • https://sieompaysdebray.fr/lesiom/txt/imgadmin/file/pivododasunodakunovevoxa.pdf
    • http://gelateriacool.it/userfiles/files/febefevipogizu.pdf
    • http://candientushinko.com/images/file/gukifusegajopisi.pdf
    • http://etenindex.nl/images/uploads/riwuwogiwavilusozuxiwuja.pdf
    • https://jf-orvalho.pt/userfiles/file/22061823425.pdf
    • http://gold-carsales.com/js/upload/files/vilimexufikogowidovumuki.pdf
    • http://mlight.cz/archiv/file/86503209094.pdf
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jelivanurojovekomubevoz.pdf
    • http://cdmatik.com/uploads/file/75162686486.pdf
    • http://blackhorsesc.pl/userfiles/file/nubikofavag.pdf
    • https://tractorpulling-emmeloord.nl/upload/file/15879378926.pdf
    • http://mosjob.ru/images/file/17200526986.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840e8ce4333---15832026181.pdf
    • http://duetsepolno.pl/userfiles/file/ledevodiliwe.pdf
    • https://vsetinrally.cz/userfiles/file/84850418935.pdf
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/ppqom1noae7mtr08fikbjq7et0/13458404782.pdf
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160856ca259099---15769952145.pdf
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160818547763db---likiti.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_off0000d6d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6D4 16792 bytes
font_01_sfnt_off0000eee6.bin
935606b2ef1be10f93ad8d6b799fe166f4cd57a1b6a969ff1415dc99c4f59d9d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE6 18172 bytes
font_02_sfnt_off00011d48.bin
15bcd8c71cf3276fb6332b87ff4e0d0142f10d51b0f3bd389e2983b645692687
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D48 10692 bytes