Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f38b45525e44e48…

MALICIOUS

PDF

72.6 KB Created: 2021-09-26 21:53:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 00d81a13b46dea12f542d5b6f0e9baaf SHA-1: 02b60abb3c2263fd69c79bc72ee9e887239c8edf SHA-256: 6f38b45525e44e48f26c3057ef767dc6520927dc6ae0feb7ab003a1d69364ca0
134 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, and it contains embedded JavaScript. The PDF also includes numerous external URIs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution campaign. The embedded JavaScript likely facilitates the redirection to these external sites or the execution of further malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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
  • 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 https://crysiq.ru/uplcv?utm_term=acr+call+recorder+unchained PDF link annotation
    • http://hiace-yoshikawa.com/js/upload/files/42355512042.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/jokinigiga.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/lowunet.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/41748901167.pdfIn PDF document text
    • http://ferien-in-zahren.de/images/file/86496169479.pdfIn PDF document text
    • https://moulindelarroque.com/userfiles/file/gafotuvazofubodijezeri.pdfIn PDF document text
    • https://srilangkapools.com/contents/files/36966351644.pdfIn PDF document text
    • http://uceng.net/_UploadFile/Images/file/52581592150.pdfIn PDF document text
    • http://skogsformedling.se/bilder_umeny/File/92564760026.pdfIn PDF document text
    • http://integrotech.pl/zdjecia/file/palofunami.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/32053874760.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/tujexirogonuxiwuvusope.pdfIn PDF document text
    • http://omeofest.eu/userfiles/files/24619505491.pdfIn PDF document text
    • http://thestarbusan.com/FileData/ckfinder/files/20210918_52B5C85272D3E093.pdfIn PDF document text
    • http://capitolmetrophysicaltherapy.com/files/files/buvegidosarixanadupavi.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/18592173786.pdfIn PDF document text
    • http://paradisetnl.com/FileData/ckfinder/files/20210908_8C2A38AF1514920C.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/zoponukomifidum.pdfIn PDF document text
    • http://combatkuntao.com/ckeditor/ckfinder/userfiles/files/385164363.pdfIn PDF document text
    • http://borik.customreal.sk/data/files/sojinelebikek.pdfIn PDF document text
    • http://yongqingtech.com/d/files/15234001583.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/6f767c84f048414018ef67f53906942c/fejubowamokugolimenubaja.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/25155164084.pdfIn PDF document text
    • http://www.agot.pl/upload/file/fuwanojoziwavofeda.pdfIn PDF document text
    • http://alfavit.tv/userfiles/file/xegipatarosinefilag.pdfIn PDF document text
    • https://daynexweb.com/upload/ckfinder/files/66830236347.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/44879183930.pdfIn PDF document text
    • http://prinsart.ro/uploads/files/wizaxapefulezulilinu.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_off0000b984.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB984 10284 bytes
SHA-256: 778db66816d7c305b8a3d2dadbb0f6ec6a6decabdaa510f10e7ae93b48cb88fc
font_01_sfnt_off0000d080.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD080 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e892.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE892 17036 bytes
SHA-256: f10d42e6880720551ca6a82b920fe2463f7d380f37ce989a0085ab9df473b692