Malicious PDF — malware analysis report

Static analysis result for SHA-256 99213c63c05c318d…

MALICIOUS

PDF

71.4 KB Created: 2021-09-20 20:45:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8f4a4f99bf3736aea95789f016f0a609 SHA-1: 800a74ddffa6bd58a80595bbdc7d56f7d2d585ca SHA-256: 99213c63c05c318dfdda0c9196664b3138e98082aedc5e69fc09c406d62494ad
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the presence of external URI heuristics further supports its malicious intent. No scripts were extracted from this sample, but the overall structure suggests a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://garglob.ru/uplcv?utm_term=clip+layer+apk PDF link annotation
    • http://wohntraumgmbh.at/47051257180.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/getogizulaxojiravawuzo.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/21969829612.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/zipunurovilufadadokelib.pdfIn PDF document text
    • http://swiss-ex.com/images/blog/file/39226462397.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133e1369507f---95323009478.pdfIn PDF document text
    • http://rivucota.com/upload/files/1852756137.pdfIn PDF document text
    • https://protrialse.eu/files/files/93853870585.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161375190d7d07---janekanu.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/81704606564.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/18753447903.pdfIn PDF document text
    • https://e-room.co/userfiles/file/49871827385.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16142d86b1e96f---65565403586.pdfIn PDF document text
    • https://kcharp.com/ckfinder/userfiles/files/vetofofugabojopif.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/zogobadosasololabutawipek.pdfIn PDF document text
    • http://gaestehaus-am-erlkoenig.de/img/editor/file/wutozagimebemekapus.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/86274003800.pdfIn PDF document text
    • https://99shayari.in/userfiles/files/buzubuvegugebipoxo.pdfIn PDF document text
    • https://net-mex.hu/ckfinder/userfiles/files/tidutebupulakexidolevinuf.pdfIn PDF document text
    • http://apismorava.eu/docs/wenafefuzu.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/161318637d7023---47396398783.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/beledaw.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/bdf485859fb6c303dfa49752d4e267f9/xeton.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_off0000b8fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD110 9992 bytes
SHA-256: 07a4cbb1b1f58a180eef01706fd47cdec37a5e0e682e8f239e8170c355161610
font_02_sfnt_off0000e750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE750 15920 bytes
SHA-256: cf51005deef4688eb324af0aa87a7417ab08482ffea960b2259c934e80717b2b