Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc178c644c4ca1cd…

MALICIOUS

PDF

79.1 KB Created: 2021-09-09 00:36:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 50bec85f856ebda9bf2426396044c47e SHA-1: 0253f40a2250520db279849f55169182cc71654c SHA-256: dc178c644c4ca1cd642eb21fba282ac6b1e4b7e29d096944757dbe330e67e337
134 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs pointing to potentially malicious or link-farm sites, suggesting it's part of a phishing or malware distribution campaign. The presence of a 'download' lure heuristic further supports this, indicating the document attempts to trick the user into downloading further content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gamboeng.com/assets/ckfinder/userfiles/files/bimonabenedogesovupuzab.pdf In PDF document text
    • https://portalkucharski.pl/app/webroot/media/files/45016166232.pdfIn PDF document text
    • http://dylogistics.com/userData/board/file/80920233387.pdfIn PDF document text
    • http://aow.infogestnet.it/ckfinder/userfiles/files/repikojojegogepamupodugo.pdfIn PDF document text
    • http://stoewebdesign.no/userfiles/file/50985676146.pdfIn PDF document text
    • https://srinivasagroup.com/ci/userfiles/files/sajitefevedikibexotiju.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210905_092531.pdfIn PDF document text
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/46832447797.pdfIn PDF document text
    • http://www.satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/80103331620.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/ludoradowenetesifapada.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/febolepamolitexenigumalu.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/koxasiwisusufup.pdfIn PDF document text
    • http://tsmsaldature.it/userfiles/files/18941606286.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613168bb5287a---pirodexejutesen.pdfIn PDF document text
    • https://skykharchono.mn/editor/files/wegizivexido.pdfIn PDF document text
    • http://haki.vn/uploads/files/42061696015.pdfIn PDF document text
    • http://61kidsclub.com/userfiles/file/93703337331.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/pegeda.pdfIn PDF document text
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/95853575968.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/161367e7ccf128---fajimupat.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/luzemax.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/fevomibutulakobit.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/55169217064.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/retoxul.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=lock+screen+removal+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_off0000d415.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD415 10544 bytes
SHA-256: f8cef2785bbb488f216a14a4e1c78933d7e3bd680c33689f6eccbdd2d6d8ba10
font_01_sfnt_off0000ec24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC24 16440 bytes
SHA-256: 40455dee6b76851e46dec253362ac7a27e1ec19eca3128a4deee82e1d9f0bb5b
font_02_sfnt_off000116dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1