Malicious PDF — malware analysis report

Static analysis result for SHA-256 dbb12a612b866c06…

MALICIOUS

PDF

81.7 KB Created: 2021-09-11 11:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: be56989ef40e8b77d58014b516adea48 SHA-1: e6737db613dd383e1af648bcd87c055513d509f0 SHA-256: dbb12a612b866c065b88ce5a26afa8018c09b26882725c72e1ec295c4f37d165
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and external URI usage. The PDF document body is unreadable, but the presence of embedded JavaScript (T1059.007) strongly suggests an attempt to redirect the user to malicious external sites, likely for phishing or further malware delivery, aligning with a Spearphishing Attachment (T1566.001) initial access vector. Numerous unknown URLs were extracted, indicating a broad distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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.
  • 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://fultoys.com/userfiles/46149953722.pdf In PDF document text
    • http://xn--c1aejbdnke.xn--p1ai/admin/ckfinder/userfiles/files/65405585207.pdfIn PDF document text
    • https://snapstudios.ca/userfiles/file/puwizotisetobijiverinopu.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613261a33927b---8675117654.pdfIn PDF document text
    • http://dhf-china.com/d/files/dixirujixipobuwafe.pdfIn PDF document text
    • https://ekinyalitim.com/depo/sayfaresim/file/wekebajuwogelasonagomiwo.pdfIn PDF document text
    • https://mrdak.cc/uploadfile/files/10106582276.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/16130ccd045977---7515602237.pdfIn PDF document text
    • https://svltv.in/userfiles/files/36850322152.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/salad.pdfIn PDF document text
    • https://noble-program.site/js/ckfinder/userfiles/files/zenodoneviwofinawota.pdfIn PDF document text
    • http://dtjxbpzx.com/filespath/files/20210904181502.pdfIn PDF document text
    • https://handientu.vn/userfiles/file/68533321269.pdfIn PDF document text
    • https://x-software.cz/data/file/rerinovazaw.pdfIn PDF document text
    • http://pedraferro.com/files/files/kalarobafulokiwanar.pdfIn PDF document text
    • https://queensflower.nl/clientfiles/voveduwunovazokinigibure.pdfIn PDF document text
    • https://dveropolis.ru/upload_picture/76087193134.pdfIn PDF document text
    • https://hunglivet.com/uploads/files/202109061745323025.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/43990115087.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/wafotabodatexawote.pdfIn PDF document text
    • https://neksav.com/upload/ckfinder/files/18505558095.pdfIn PDF document text
    • http://andersonlawdecorah.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tosamizofu.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021090709155273499.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/88639328166.pdfIn PDF document text
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/rawanunurazirevifopod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=sound+of+o+with+picturesPDF 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_off0000d928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD928 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f13a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF13A 18096 bytes
SHA-256: fc31fd23c173014c582287b40a2f3619d6944567fd26ba08d2d7fd4058f477fd
font_02_sfnt_off00011ff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF5 10768 bytes
SHA-256: c366ce86b545e634666973dea265d378057638b77c80c80dc9fb1a32f16fe8c9