Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a76bc184b4d1f03…

MALICIOUS

PDF

89.6 KB Created: 2021-06-29 04:41:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dd5587a3da4c72feca49cef449365a93 SHA-1: c76ea0deb0aa4520cfaa9a2c79b1ecf7c3e8a120 SHA-256: 4a76bc184b4d1f0366503257bc654657871cd39320d667b1cf3a237328940b36
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.001 Process Injection

The PDF contains numerous external URIs and link farms pointing to various PDF files hosted on different domains, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious link farm designed to lure users into downloading further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://infrive.ru/uplcv?utm_term=conversion+factor+table
    • http://funperm.ru/content/file/15614143139.pdf
    • http://jamessham.com/admin/usercontent/file/dizawug.pdf
    • http://vivatbacchus.hu/files/file/zademi.pdf
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/89b69f9c15f648e9c0cbd26c3fb2cbd4/devebijivazifuxepamubid.pdf
    • http://psychoterapia-przemysl.net/img/userfiles/file/nawaxol.pdf
    • https://digireg.nu/upload/84517093801.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b0c8debf39---23428096143.pdf
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/6jocll7pngkttc259bk1qi5mc5/53503533490.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/976dca760fc74316e762251c6ae8627b/30771106490.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/6rltd80ghuaemmot7jmaognbhq/83033877687.pdf
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6200c4018---41757618589.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/6093b2aff6096bf3c00bda1246d0fd6e/zuriwunizob.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608629c42b0a2---xumazalepufujatovin.pdf
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/854f46a0bfcaec7a49d26566beb49cdf/29852099172.pdf
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c6fb17ac04---8803528160.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/e412d2b08c2b4f3d9c2aba2953d5b523/segus.pdf
    • https://burmesecatclub.nz/wp-content/plugins/super-forms/uploads/php/files/13fba8e65e275a97a448f4c803e22402/98695983397.pdf
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160770c5928284---76506245022.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16090ac4dc8fb4---58094928650.pdf
    • https://thedestinbeachhouses.com/wp-content/plugins/super-forms/uploads/php/files/57ff1f1a34ddace75ebe78c665fa0528/86601674916.pdf
    • http://simmsfamilyreunion.com/clients/9/98/98d47f1658d09d39d77ba56043454c9c/File/62361226916.pdf
    • http://princeworldwide.com/multimedia/userfiles/file/65591550703.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2e9c532092---dikamado.pdf
    • http://fittbikese.hu/files/file/2425397871.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_off0000fcb3.bin
33fa30966670c3aa205c9dc10ebbecece306f3f00c8ea5ebf96cafef1c21e086
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCB3 16996 bytes
font_01_sfnt_off000128ba.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128BA 16792 bytes
font_02_sfnt_off000140d1.bin
f944e73d234fc7e64e7b533f22341d34b17a9ef831860f3ea019712c1db09c7e
pdf-font-stream PDF embedded font (sfnt) at offset 0x140D1 10568 bytes