Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3b839a89e7ea7a7…

MALICIOUS

PDF

69.5 KB Created: 2021-10-03 00:01:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e3e6dec8c95ef581e345f6a71637d9f0 SHA-1: dc6d5650963584724b3eee6300ad79cf51719ee9 SHA-256: e3b839a89e7ea7a7590f6f09d52245eb5572fc79ae0e8138a71ae18ae16b0890
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous distinct domains, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct content clues, but the presence of many external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nikosdimos.gr/userfiles/file/79467913154.pdf In PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/mafog.pdfIn PDF document text
    • http://mkbeauty.vn/luutru/files/79103549259.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/65721715050.pdfIn PDF document text
    • http://www.weilandensemble.nl/ckfinder/userfiles/files/16522042073.pdfIn PDF document text
    • https://gaseg.com/wp-content/plugins/super-forms/uploads/php/files/vk0v903qa98aujuqph26n39th0/74843856584.pdfIn PDF document text
    • https://skiclubraonbaccarat.fr/pdf/lofikizudanebu.pdfIn PDF document text
    • https://tanhaithanhvalves.com/quangcao/admin/file/8266908734.pdfIn PDF document text
    • https://deverfgrossiercms.deindrukdemo.nl/upload/files/43734549794.pdfIn PDF document text
    • http://sea-cruise.ru/ckfinder/userfiles/files/7036959994.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/28381305346.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/nijiwesubimemapidasumajug.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/86b214cdfd44287c661a58ac87aa9687/tebafo.pdfIn PDF document text
    • https://xn--dokumaanahtarlk-llc.net/userfiles/file/29790299362.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/zivulisutawiwipikolixopu.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/81411073599.pdfIn PDF document text
    • http://horizonpestservices.com/userfile/togixupolikudoxu.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/39673215968.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/bakufaguvopuraruraleguri.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/45594441187.pdfIn PDF document text
    • http://tolgyesvolgy.hu/userfiles/file/gakelop.pdfIn PDF document text
    • http://nenorm.com/files/files/bipidunajizu.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///92090364599.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/pisagat.pdfIn PDF document text
    • https://5uempat.com/contents/files/kasazojizelewupipunar.pdfIn PDF document text
    • http://chono.mn/uploads/userfiles/files/99722851680.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+report+t+test+results+in+a+table+apaPDF 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_off0000b0ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CE 10564 bytes
SHA-256: 6df1cbc06f5cadb4fcaa32edc08fc133a141097b2e8cf21df803c96f3339e04e
font_01_sfnt_off0000c8cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8CB 15500 bytes
SHA-256: 84fe9cc15930d9122095097b7758ae2a80a991cc0dc9f7fa752b6c2f66f4872d
font_02_sfnt_off0000f02f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1