Malicious PDF — malware analysis report

Static analysis result for SHA-256 56d71b36e486da41…

MALICIOUS

PDF

80.8 KB Created: 2021-09-13 15:13:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 402967b8811ad8ddcb5b8fc3e90930f2 SHA-1: da5978b445bed58a253f20e8bb2c6c8da033a255 SHA-256: 56d71b36e486da41a7792884e8b33d39c752c6d4c4a152f95a97a53350dbf4c5
104 Risk Score

Malware Insights

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

This PDF document contains a link farm designed to direct users to various external resources, some of which are hosted on compromised websites. The presence of embedded JavaScript and the ML classifier's high confidence score indicate malicious intent. The primary goal appears to be to facilitate the download of further malicious content through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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 http://bajcsidavidfoto.com/_user/file/53864690767.pdf In PDF document text
    • https://bywuf.org/upload/editor/files/6966940716.pdfIn PDF document text
    • https://jjcfurnituremaker.com/userfiles/files/99632723979.pdfIn PDF document text
    • http://vinhthuan.vn/upload/files/rexeloji.pdfIn PDF document text
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bb16aa97a4---24234164253.pdfIn PDF document text
    • http://www.ville-civaux.fr/admin/js/ckfinder/userfiles/files/67574454503.pdfIn PDF document text
    • https://www.ijdsir.com/ckfinder/userfiles/files/52495656798.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/67c8a30775e26347168f666fcfffdf9b/39364179034.pdfIn PDF document text
    • http://tw-echen.com/uploads/files/202109040851141587.pdfIn PDF document text
    • http://helloslow.com/data/userfiles/files/miwonidopubuxamixomibisi.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/57685893814.pdfIn PDF document text
    • http://mexxeopaint.com/upload/files/xakolokopawo.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/1718005139613a85c07566a.pdfIn PDF document text
    • http://jmyhship.com/uploadfile/files/getuletenime.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/96brksonjmk85nfgqosep9kjg1/14549987696.pdfIn PDF document text
    • http://langyupharm.com/upload/files/14872301202.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/samomagurimasupesiri.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/belobitum.pdfIn PDF document text
    • https://10glazsikeyrosa.ru/file/78983051984.pdfIn PDF document text
    • http://pbhdom.eu/userfiles/file/borowofogiribajunipo.pdfIn PDF document text
    • http://4darchitecture.org/img/all/88522322990.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/funizipekoxefelikimeda.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/tuferu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=tekken+6+mobile+game+free+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_off0000d6f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F6 17268 bytes
SHA-256: 71ed41fc5d727f533f1b902aade345c38a731bb189e00924a3d848fe8cdf766a
font_01_sfnt_off000103e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011bf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF7 10880 bytes
SHA-256: 6f592555aad0cf5328a8fbe5c70648cda17a1c6df7f6624bd7fdeee0979f0a6e