Malicious PDF — malware analysis report

Static analysis result for SHA-256 e123e81b1b854a89…

MALICIOUS

PDF

86.2 KB Created: 2021-06-28 00:55:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: db0d70bd07d966ea06a059212390e8cd SHA-1: a5a9223711011100af449de0f8ef950fdf1f288e SHA-256: e123e81b1b854a896bb9aee3ed3de91c31d0bcd1da74d1e50b7dcfbde03f8f70
96 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to distribute traffic or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://cructi.ru/uplcv?utm_term=john+winchester+journal+pages+pdf
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0b5857799---23489163978.pdf
    • https://xn--interpeas-r6a.es/upload/files/38522894948.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160aae3b0179a4---jijeda.pdf
    • http://fonnepal.org/userfiles/file/66304294612.pdf
    • https://laplacedesstores.com/upload/file/69547333396.pdf
    • https://protechlighting.com/wp-content/plugins/super-forms/uploads/php/files/665a0b3b22a499624472ded74b88b75e/22252572684.pdf
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ac83e90e9fd---dawamosed.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160cb754a28e98---49792473428.pdf
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba9f6e68a3c---taxuvixusu.pdf
    • http://architettoseneca.com/userfiles/files/30412566001.pdf
    • http://bvsaigonbinhduong.vn/uploads/files/muwefojevuxive.pdf
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/fde7cca179d38982d2176d0ba385b4dc/52134223776.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/31cbe44b116a45b98a338a4737c3cd0c/17355042017.pdf
    • http://jmvlpslimited.com/ci/userfiles/files/61852483317.pdf
    • https://cplastik.cz/data/cms/file/tonobagalawerenuraz.pdf
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/c1vhd5rvhtoo009f2jrugolnd7/29290274211.pdf
    • https://dietacud.eu/upload/file/87670903838.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a30d5d2c422---98983787248.pdf
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940433c2da2---tabotiporugofawadif.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf1fa18afcb---68580462026.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5c1539734---6735335065.pdf
    • http://ventilatoryzlin.cz/images/file/dederutuwakivole.pdf
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4b5ae4e47---92385958502.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/a451a79a22c1ecee9a2d75f2c16dc895/juduravub.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_off0000ed59.bin
084f71317c535ca0fb3cc327a888ffa08b97af33a8d03995c2dcc183e8116a54
pdf-font-stream PDF embedded font (sfnt) at offset 0xED59 16400 bytes
font_01_sfnt_off00011788.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11788 16792 bytes
font_02_sfnt_off00012f9f.bin
fa5f71707bf5640aeec10a5dcb9c9151f12584573d6dc7717605ca15781306c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F9F 11204 bytes