Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f65aa4eff78bdcf…

MALICIOUS

PDF

94.4 KB Created: 2021-09-09 22:44:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e6699df139c59f75f71d0d5f9e046229 SHA-1: 405f7ab96fc485c59f1c56a0ce672787dab041b8 SHA-256: 4f65aa4eff78bdcfd4946b5688c87334948950b7f21d89baeba038c1bc4d213d
204 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript and is flagged by multiple heuristics as malicious, including a high-confidence ML detection and ClamAV. The 'SE_FAKE_CAPTCHA' heuristic indicates the document's primary purpose is to deceive the user into performing an action, likely to execute a malicious payload. The presence of numerous external links, many pointing to compromised WordPress sites, suggests a phishing or credential harvesting attempt, potentially leading to further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16132a04aa1268---bugagikolapodasamijo.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/28c337b123ceb746fa307f0d30087ac4/jezonaxeb.pdf
    • https://robertbah.si/files/file/31990243047.pdf
    • http://obras.ru/sites/default/files/uploads/20793058571.pdf
    • https://webmenuplus.com/images/file/zixitomena.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161396591496d1---17393668864.pdf
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161319f21b766c---83828907568.pdf
    • http://vasset.bg/userfiles/file/rabezarewujusiwefutibeb.pdf
    • http://sendedianqi.com/upload_fck/file/2021-9-4/20210904004722449430.pdf
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/aiikaqc6na2ura7qdlt2ect9cu/juzibupetajafutafigog.pdf
    • http://mottaing.eu/userfiles/files/sopitemod.pdf
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/43345509715.pdf
    • https://vespaclubcagliari.com/userfiles/file/99171373115.pdf
    • https://norservis.com/files/files/duromedovutotosowabal.pdf
    • http://autosoftware.company/autoresponders_images/files/xogubesorikaralas.pdf
    • https://pointwebhost.com/calisma2/files/uploads/vutafurusasiremu.pdf
    • http://fxlcd.com/upload/file/mezoroso.pdf
    • http://diysmart.net/userfiles/file/dikimogazorasaj.pdf
    • https://ubk-sad.de/azubi/userfiles/files/75674354324.pdf
    • http://litho-and-co.fr/ckeditor/upload/files/demefobilakor.pdf
    • http://teen.plovdivweek.com/js/ckfinder/userfiles/files/gedalutefosovologul.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/161356c4e49cbe---71086566955.pdf
    • http://creaorganization.com/depo/sayfaresim/file/37280302334.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=dragon+city+cheat+codes+2020
    • 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_off000108de.bin
32718e76fecdfb0a52c4546faa3c6d3ff6535bf5d9cef1364ae9135f37498705
pdf-font-stream PDF embedded font (sfnt) at offset 0x108DE 19156 bytes
font_01_sfnt_off00013a99.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A99 16792 bytes
font_02_sfnt_off000152b0.bin
490255b5997cf3cd9ab405cf7f73865bd32a24937f5f55432a7970fdbf1e2c37
pdf-font-stream PDF embedded font (sfnt) at offset 0x152B0 10960 bytes