Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8cf8cb030d24a22…

MALICIOUS

PDF

81.0 KB Created: 2021-09-19 15:05:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: fcae7806ae0d31953b4c3c0be34dc91c SHA-1: 601d46e661c9292bd45ad4d9592731c90bd56858 SHA-256: a8cf8cb030d24a22f995386608f62df592000a974eee25c5d98330c3380c9659
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • 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://soleilboo.com/images/uploads/files/xosatapovusifujozos.pdf In PDF document text
    • https://mongolia-volkslift.com/uploads/files/revud.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/luxixebam.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/fusolasajaviwuxofuz.pdfIn PDF document text
    • http://dreambeauty.kr/upload/fckeditor/file/66898589023.pdfIn PDF document text
    • http://cbstav.cz/file/dubetoja.pdfIn PDF document text
    • http://ux02.wadhost.com/js/ckfinder/userfiles/files/26310783203.pdfIn PDF document text
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/ihde3s4j52tqrl38pg76qvpm9q/77448381649.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/88965858669.pdfIn PDF document text
    • http://cu-mbc.com/ckfinder/userfiles/files/69496893823.pdfIn PDF document text
    • http://1night2daytour.com/ckupload/files/julotimebu.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/wexikewefimat.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/25009262701.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/nasut.pdfIn PDF document text
    • https://www.antoniopopolizio.it/ckfinder/userfiles/files/19546253113.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/161312c45d7cc9---mudidukovitibip.pdfIn PDF document text
    • http://ptk-astana.kz/wp-content/plugins/super-forms/uploads/php/files/e1de6746a930a66ceffe25960518a482/dujifi.pdfIn PDF document text
    • https://fcksa.com/ckfinder/userfiles/files/najubixevukevazajimerol.pdfIn PDF document text
    • https://et-auditing.com/userfiles/files/kobumowazisinemebuwar.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/029ed0797bd0200a13c87f968728d109/wufoxaloremilafi.pdfIn PDF document text
    • https://oancora.com/ckfinder/files/wolov.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/98864269023.pdfIn PDF document text
    • http://vip-cond.ru/userfiles/file/23715462271.pdfIn PDF document text
    • https://razredna-nastava.net/files/fubuxa.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/50259030817.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=drag+racing+mod+apk+downloadPDF 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_off0000d942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD942 10640 bytes
SHA-256: 08bdbfc01da2ff22dff9c9b2f26c7a3ce635b03e557cd7136637e13520cc0650
font_01_sfnt_off0000f158.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF158 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001096a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1096A 17412 bytes
SHA-256: 0b45bc8f82ec467fd7ff2480533a7c0264d8e987ec4e0fcc47022ac6bd23b1fc