Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5549dee4d7065d6…

MALICIOUS

PDF

71.4 KB Created: 2021-09-25 20:07:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9d0897b953288605a33d6fa1e614aead SHA-1: eca46aa3e37a19e82072c986031d4e0de43a0cae SHA-256: b5549dee4d7065d61b25769fc98e1dd3c19fefde6b41b18d231fda3f80be7c20
136 Risk Score

Malware Insights

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

The PDF document exhibits characteristics of a remote support tool lure, instructing the user to install or connect with such software. Numerous embedded URLs point to various PDF files hosted on compromised or disposable domains, suggesting a distribution mechanism for malicious payloads. The ML classifier strongly indicates maliciousness, and the presence of multiple external links supports a phishing or social engineering attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://drafthe.ru/uplcv?utm_term=teamviewer+android+app+download
    • http://splogservice.ru/content/file/17807843924.pdf
    • https://laatjehuisweerstralen.nl/upload/file/84059222523.pdf
    • http://testplanet.nl/uploads/files/popug.pdf
    • http://omonetach.pl/foto/ilustracje/file/42625721584.pdf
    • http://dulichtantai.com/files/uploaded/files/23748773490.pdf
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/fb32bde8256711805e093428fd272496/35846683329.pdf
    • https://suativisamsungtaihanoi.net/upload/files/97911793332.pdf
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/rorinamoxab.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/161466f78b8c59---93735825598.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613d20321eb09---94321398037.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614113cf3c7b1---7452811565.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16145e827049c7---rusinazibazaridede.pdf
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/dawunarejo.pdf
    • http://cosonhuath.com/hinhanh_fckeditor/file/fesokotedelorupagefikuvef.pdf
    • http://osmed.cz/app/webroot/files/files/xavevizivuro.pdf
    • http://quaisetoiles.fr/img_pages/file/89983939755.pdf
    • http://uceng.net/_UploadFile/Images/file/79445250325.pdf
    • http://denetimmusavirlik.com/userfiles/file/fikosomogujepanepefofo.pdf
    • https://giyimkent.formenemlak.com/upload/ckfinder/files/kafejoneniberosisanov.pdf
    • https://inprovitargentina.com/ckfinder/userfiles/files/komajopudalodize.pdf
    • http://cnkls.com/userfiles/file/1631791786.pdf
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/2fee6ad784574a6199f3e7cb27977c81/xifezowujopapelepen.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16146f5394306b---tusodek.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_off0000b462.bin
ff5789cbe96dce161a2695f96d666337f401cbf674096fbb1713841c210f1697
pdf-font-stream PDF embedded font (sfnt) at offset 0xB462 17432 bytes
font_01_sfnt_off0000e084.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE084 16792 bytes
font_02_sfnt_off0000f89b.bin
a4f120dcedf33507eaa6efad56ecc669f52e02721fcbdf62e09d577b830af118
pdf-font-stream PDF embedded font (sfnt) at offset 0xF89B 10400 bytes