Malicious PDF — malware analysis report

Static analysis result for SHA-256 2253a8787d1279e6…

MALICIOUS

PDF

91.1 KB Created: 2021-08-05 20:17:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 527f3742a8e75dedd1b582898940c839 SHA-1: 4d51075b4434047234fa9502356c843de279df20 SHA-256: 2253a8787d1279e6b410476b9484d2b427a4f1905fb8d24e33e17fa2148aae53
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these external links. No scripts were extracted, but the structure and URL analysis are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://omgmediatank.com/userfiles/files/76390491562.pdf In PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/nuwufajerer.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/46ec3eaa9e77a193fc55b2d380f1e455/kurus.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/de2nb5n4l17llhjvttbv6jdtvd/sesujapuvapelew.pdfIn PDF document text
    • http://philboyd.com/21966649120.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/66251431356.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/7a5c0b836ba9935e4d4bb130b782b868/23443791440.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/bcc919e7d00d73580dba86c48ebb2a2a/12388550449.pdfIn PDF document text
    • https://eprobatdz.com/ckfinder/userfiles/files/93099160149.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/biwusepezumonag.pdfIn PDF document text
    • http://cosmikkino.ru/sadm_files/vivepadaxapixifolujug.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/5c1e45858978b8125d72ef723dfbd55a/bubiwigebewukikomabas.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/e089a3e102876f86ec5ae6ff18c29f4f/dupolupojalijegotu.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/a3727ac0139982e7d4367bcedaceec8e/39410146753.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f37559dce05---pasupowi.pdfIn PDF document text
    • https://astoriareiki.com/wp-content/plugins/super-forms/uploads/php/files/ad6a2a5785a417ed0cdf1a8aa5f339f9/xoripabifovuzodawidese.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/76804f608873c0af81ece2f1a37e6372/kepiw.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/bapinojopeposomujavit.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1dbd6a2187---33926344604.pdfIn PDF document text
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/hju5jtl0m0lctmb8r110ll7m3a/vamezedi.pdfIn PDF document text
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/528311514.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/bovafofonexen.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/gotujelegupepodaledo.pdfIn PDF document text
    • http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609256384bd4d---14294398748.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/191989318608af7d8c0e14.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=philips+respironics+dreamstation+go+auto+cpap+machine+with+heated+humidifierPDF 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_off0000fe24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE24 11252 bytes
SHA-256: 092100f4a4e6cad668102544fd2ab27e9c297a3540b396f472a291d7f11f839e
font_01_sfnt_off00011834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11834 17376 bytes
SHA-256: 46ee807fb0794f865310e1b74c06881fb95811230f110564a59ff5045c64b516
font_02_sfnt_off000145d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1