Malicious PDF — malware analysis report

Static analysis result for SHA-256 ebd10f84221e2b90…

MALICIOUS

PDF

96.6 KB Created: 2021-09-24 09:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f4b9f995554b9a6466d6388910242046 SHA-1: 763e4c4b89dbab913b4aa03cc4e1445c35530a2b SHA-256: ebd10f84221e2b90ab5d201642b753255155e6adcd73b0682e6aaecd1995ddd7
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://dietgame.net/admin/fckeditor/data/file/20210924092852.pdf In PDF document text
    • http://rbtyutj01.com/userfiles/files/97156418530.pdfIn PDF document text
    • http://ydis.kr/userfiles/file/140437164869.pdfIn PDF document text
    • https://yocarbroker.com/upload/ckfinder/files/30087582648.pdfIn PDF document text
    • http://www.reeder.ee/files/filemanager/zukufis.pdfIn PDF document text
    • http://www.first-classlogistics.com/image/upload/File/puvepazofosakigopedi.pdfIn PDF document text
    • http://africalegal.nl/userfiles/file/borojibolizaralezo.pdfIn PDF document text
    • http://ledlight-lamp.com/mingyi/images/userfiles/file/73551292480.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/97867618543.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/53183060628.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/21266694220.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161404dd9a1893---nudodexonulekogatenop.pdfIn PDF document text
    • https://alident.centralcms.cloud/galeria/files/disepefivomo.pdfIn PDF document text
    • https://777mto.org/contents/files/zorakazigixojaf.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d0da97e47b---boxuburemipawodow.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161369d9b259d5---73320119817.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/5cmjhs7omlgdkt0t2o363mccdf/42582714472.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/tafizakobimutoxedonigow.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614be40c30ed4---34143193420.pdfIn PDF document text
    • http://cmorshomecareassociates.org/uploaded_files/userfiles/files/44228138346.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210916_0FFF9790704D1C90.pdfIn PDF document text
    • http://obchodsezlatem.cz/upload/files/vafalusagofonojobet.pdfIn PDF document text
    • http://cariboohose.com/userfiles/file/supudawejofutivejag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=custom+notification+sound+android+studioPDF 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_off000115d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DED 10588 bytes
SHA-256: 10e6298e78d2705e58d5b3c9a0851353f7303b3e6608dd2c8d2a94943a351a6e
font_02_sfnt_off0001461d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1461D 18104 bytes
SHA-256: a4c5c2ca78f95b20e7ea51dbd002aa7a91056c7e60d1cdad598396566a2e6557