Malicious PDF — malware analysis report

Static analysis result for SHA-256 6caf273d81cf1999…

MALICIOUS

PDF

77.8 KB Created: 2021-10-09 23:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: fd3530fa97248eff619a907fdfe338fc SHA-1: 53d87cad01e58ce005592dc3b959df1ad1b4e378 SHA-256: 6caf273d81cf19990c76bbdfe823c133e9f2dfd76b59756471afbe9c0c4d17a6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by multiple heuristics, including ML and ClamAV, as malicious phishing content. It contains numerous embedded URLs pointing to suspicious domains, suggesting a phishing or malware distribution campaign. The PDF structure and embedded links indicate it's likely part of a spearphishing attachment campaign aiming to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cructi.ru/uplcv?utm_term=dissertation+proofreading+services PDF link annotation
    • http://rootbeadmill.com/upload_fck/file/2021-9-20/20210920191230834975.pdfIn PDF document text
    • http://schule.havonix.com/ckfinder/userfiles/files/bumijonagefupov.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021100912483176.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/ninilibuwutubumisotetepet.pdfIn PDF document text
    • https://bizimpin.com/calisma2/files/uploads/72272497228.pdfIn PDF document text
    • http://fulns.com/uploadfile/fckedit/file/1631521789dea2.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/mavifo.pdfIn PDF document text
    • https://pianoinprimopianofestival.com/uploads/file/99219946707.pdfIn PDF document text
    • http://patrick-jardinage.fr/ckfinder/userfiles/files/puvafolo.pdfIn PDF document text
    • https://arabadvertise.com/userfiles/files/83759363208.pdfIn PDF document text
    • https://felicityokolo.com/file/41123570163.pdfIn PDF document text
    • http://yas-center.ru/userfiles/file/49252038662.pdfIn PDF document text
    • http://librojuridico.com/aym_images/files/3155485103.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/rorixum.pdfIn PDF document text
    • http://emilybarnes.com/DEVELOPMENT/VERSIONED/emilybarnes/trunk/sites/default/files/file/kalamarotoritorakifagoni.pdfIn PDF document text
    • https://tumsad.org/img/editor/image/file/dozojorelapolebumufod.pdfIn PDF document text
    • http://laguna.piyawatgroup.com/images/files/65545007598.pdfIn PDF document text
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/novijufizefomerogexato.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/7453477843.pdfIn PDF document text
    • http://4seasonstours.in/userfiles/file/23744517168.pdfIn PDF document text
    • https://ww170002.linebot.net/upfile/files/20211005113122.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/gapodigoboniwe.pdfIn PDF document text
    • https://vibangthuaphatlai.net/uploads/files/52161823908.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/14240813226.pdfIn PDF document text
    • https://b2cdemo.tickets.com/content/files/tulovasagevawefunepe.pdfIn PDF document text
    • 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_off0000cb23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB23 17556 bytes
SHA-256: a0116f0cc0ff058399e6c214cd210b668bc0f07e73f80d600e93368ea8601fca
font_01_sfnt_off0000f7f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F1 10816 bytes
SHA-256: c7c33a782b3fe4916d2325c35d77747fb68a6a4e2f80f89bf67067e6cee5ecff
font_02_sfnt_off000110e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1