Malicious PDF — malware analysis report

Static analysis result for SHA-256 d56d5c84def432cc…

MALICIOUS

PDF

81.4 KB Created: 2021-09-12 08:54:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: da376e571dbd72acf84bb983444ce1a9 SHA-1: 9dae4b0c790ea66ab65feb5eb9ec6eb0c42832cd SHA-256: d56d5c84def432ccfa288732fe0ae0bf2973c5aab9bd2b8782997d2dc7c9b054
134 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with multiple embedded URLs pointing to PDF files, suggesting a phishing or malware distribution scheme. The presence of a 'download button' lure further supports this. No scripts were extracted, but the overall structure and detection results point to a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://kungfuclasshongkong.com/louis/taichi/ckfinder/userfiles/files/xujeseretut.pdf In PDF document text
    • http://files.ibiza-ferien.de/file/67959308842.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/43061664652.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/161328a5ced183---fizenevip.pdfIn PDF document text
    • http://topstec.com/d/files/gajazuxagemiwobabage.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/joveguziraniv.pdfIn PDF document text
    • http://bud-med.eu/userfiles/file/79297514316.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/pivefanalareguzuwev.pdfIn PDF document text
    • https://asiapharma.la/files/files/nidusokugezi.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/wepudaletaxaz.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/74168747401.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f4e35405a---2828099551.pdfIn PDF document text
    • https://er-cardiff.com/eurostyl/photos/file/25295006127.pdfIn PDF document text
    • http://nhagiatxanh.com/public/default/ckeditor/files/loluveneb.pdfIn PDF document text
    • http://bong-dem-long.org/upload/editor/files/sazazumulakibi.pdfIn PDF document text
    • http://webs123.com/userfiles/file/90169983571.pdfIn PDF document text
    • http://royalwedding.jp/images/blog/file/97514957678.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/mizuwolepesivu.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210904170023565.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/xorikusoro.pdfIn PDF document text
    • https://comillaspostgrado.es/userfiles/file/lelajoxumekabetes.pdfIn PDF document text
    • http://chagatea.ru/wp-content/plugins/super-forms/uploads/php/files/fa37e844a4f95631aa6230c32418e25d/sojunosodosikisunafezasa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=panel+app+apkPDF 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_off0000da8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8A 18480 bytes
SHA-256: d68606bfd27dfcf70a3deebe4463b2e7756a884bc463cb1686986aa9ed25cb56
font_01_sfnt_off00010ac6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC6 9760 bytes
SHA-256: 031d19714c917c460a15311d4f75f8376878867880cf33ebc5da6a639f2c86ca
font_02_sfnt_off0001202e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1202E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1