Malicious PDF — malware analysis report

Static analysis result for SHA-256 94cd3abdc278cd27…

MALICIOUS

PDF

85.4 KB Created: 2021-07-19 11:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: b365082c7dcc3526059fbadff3ce91e8 SHA-1: a0cb18b604d31bd106224fb2ed03efca3414330e SHA-256: 94cd3abdc278cd278be60c2e1181e90fa8d7ff611b62672ed1c5c689802eb3b2
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16085ff033b2ef---69461126629.pdf In PDF document text
    • http://ahcxdq.com/uploads/file/290045066150.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/9f8c0b364ae5dfe2fec51d8ef3dbc060/mameva.pdfIn PDF document text
    • https://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076b7ebbb50f---loveber.pdfIn PDF document text
    • http://zezoalza.com/ckupload/files/83517679409.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/87664336376.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/5339bf29f9d3bce4cddf4dfad199206e/95794974151.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/rufowedagapefo.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160989a5d82920---zofadokubigolikarufugus.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/vodulikiruvoxakonex.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/30159127182.pdfIn PDF document text
    • http://pinturasoltra.com/images/slider/files/joben.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/moguwuvemas.pdfIn PDF document text
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/5oti2ngte53jlg1qsuffa9u1r8/wumanagedubi.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/bakipepiwukivetujoxosod.pdfIn PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160915a48e6c63---83245421829.pdfIn PDF document text
    • https://x-software.cz/data/file/zanedofujemirozaza.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/dhsqu0ooj21arqveivaml67u20/bumonizibibifo.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/zafanemi.pdfIn PDF document text
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609f364f186d0---muxuvidavukesuposog.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082ff8136e77---worigonefilegawavu.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/napojibaropugezixidirisa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=wordly+wise+book+8+lesson+14+answersPDF 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_off0000e986.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE986 17152 bytes
SHA-256: 2e0a4fe499eb2d1f760dcd18681784dde0d8c99c6abd8f187beb1cab1bf9acba
font_01_sfnt_off000116bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116BF 10904 bytes
SHA-256: 75d225721bbb8a6c197c3e12768748f08a7c6e6f5f611a5cc56e07d3121da850
font_02_sfnt_off00013037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13037 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1