Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa51839797c2774…

MALICIOUS

PDF

79.9 KB Created: 2021-06-27 06:36:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e2e5066fbf158434d73402eca243b436 SHA-1: f15dd5cf78c31d4389ac41b03192759d34622d78 SHA-256: 4fa51839797c27742b2e1ddde86b78e660d95a42f89e1d6dd15017024bfcebfb
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting domains, 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 intent. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the exploitation of user trust through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://tabularasa.lv/sites/tabularasa/uploads/documents/files/90962668472.pdf
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608bcfd8e5abd---ravokiga.pdf
    • https://alrashed-alsaleh.com/userfiles/files/43667386513.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/isn028r4nliucn6ujeldb11i84/84708349632.pdf
    • http://talleresjpg.es/img/file/gadulojedomu.pdf
    • http://forter.vn/hinhanh/file/43465575520.pdf
    • http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608738d609d50---sibenazulafujidogexevavar.pdf
    • https://laurallo.com/ckfinder/userfiles/files/xijexawasenexevifadu.pdf
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076fe69753a9---titixad.pdf
    • https://chiataiec.com/userfiles/Proj_Name//files/vesololibedila.pdf
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e85e2e7e7---53375759519.pdf
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/08c474409426687f18a439dd88e18354/webazutotivivemu.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5c6fcb8d0---polamu.pdf
    • http://vom-ragnaroek.de/uploads/file/nalaritejejufu.pdf
    • http://lateonsettay-sachs.org/userfiles/file/19600172149.pdf
    • https://trellisdundee.com/wp-content/plugins/super-forms/uploads/php/files/fa95038f4437a55b69e597047c4a00c6/nuvupajilurexizujepe.pdf
    • https://asset-books.com/userfiles/file/dumazojazuxuloluvazumo.pdf
    • https://dptech.vn/uploads/files/fewidojog.pdf
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/40ab0ef580280d6e06b5aa24a9610f84/26893729696.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608944be7529b---63804769818.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16082234b6402d---41019249859.pdf
    • http://ccforum.kr/uploads/file/1622284183.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=untitled+jamboard+online
    • 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_off0000d41c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD41C 16792 bytes
font_01_sfnt_off0000ec33.bin
f5a823399c645eb13a02fe334d8ab944a394f4c844c8f1dc4232527def51e79a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC33 10516 bytes
font_02_sfnt_off00010403.bin
645c0771932715f5686f42814cab7352fa3c8eaf60d2ecd8a6fe06c27d4c8f16
pdf-font-stream PDF embedded font (sfnt) at offset 0x10403 17764 bytes