Malicious PDF — malware analysis report

Static analysis result for SHA-256 a001863ff3288b48…

MALICIOUS

PDF

86.4 KB Created: 2021-07-18 23:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 390e976b8fcd4df0686948d07feffd14 SHA-1: 99124289591ba06e9e31d4156f33b0cde8f151ae SHA-256: a001863ff3288b4809bc1544674b049d91fd5fef1715610b946651b23524cb1e
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and a significant number of external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed for redirection. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent to lure users through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • 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 http://mizuho-co.net/file/ck/files/82186767753.pdf In PDF document text
    • http://mea-travel.pl/userfiles/file/vinenewoxaserim.pdfIn PDF document text
    • http://nhs71.com/clients/d/d9/d9c6bfbc4bbdd207836d30c01fe5869c/File/6961970274.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/futofanu.pdfIn PDF document text
    • https://quangcaowebsite.vn/uploads/files/varesekezo.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/xitub.pdfIn PDF document text
    • http://rld-carbon.ru/file/37014964890.pdfIn PDF document text
    • http://studiogiamberardino.it/userfiles/files/tuzutarujapelifet.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/rudodabigufixu.pdfIn PDF document text
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sadatimavufezozuvelop.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb0ffa9024---loluk.pdfIn PDF document text
    • https://0a3exp.com/upfiles/editor/files/78188726894.pdfIn PDF document text
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d1a00316fa---xamefuraxozagadop.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/kukamafil.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/abkpnukc4kp71ij3t2729rdeip/fuxigoji.pdfIn PDF document text
    • http://shiinamotors.com/js/upload/files/44142825977.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/80707164039.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/rerovufefofinukaguda.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/9621d09f2218c7159064839736cb7396/laled.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/c2d3a4a8f78516c62bfabe9c505fb6a7/34876370251.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/durisabij.pdfIn PDF document text
    • http://www.lugashotel.com/data/editorfile/sofofofijuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=it+code+402+class+10+notesPDF 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_off0000eeec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEEC 17504 bytes
SHA-256: 7afd0745eb0e5d7641af2ccb59d51fc73ebf51ccdc6e0568501a0c6ee30a955e
font_01_sfnt_off00011ca9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CA9 10496 bytes
SHA-256: 195d9f8f7f07591d7481769555a6a989f6ac65fd823034f7df6835aff81950e1
font_02_sfnt_off000134cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1