Malicious PDF — malware analysis report

Static analysis result for SHA-256 d506e2356d904291…

MALICIOUS

PDF

101.3 KB Created: 2021-08-08 06:33:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 25c2d2e85defce2389d4e75fb709a6d5 SHA-1: 904160a96f7ca055ae63bdaeb9b2f2a82eb17c62 SHA-256: d506e2356d9042915c33d2a4e36d6997e316a83de8a95d687b87ec6d016a05e1
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and heuristics identified it as a link farm on disposable hosting. While no scripts were extracted, the nature of the URLs suggests a potential for hosting malicious content or facilitating further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://skrabl.pl/www/rpbd/fck/file/kesudewotojef.pdf In PDF document text
    • https://advik.net/userfiles/file/73300887522.pdfIn PDF document text
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/0boere3e0orduhp6uvtv1t9nnj/suxelepodosa.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/foweneta.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160839b377fbd9---vadinubopupalofe.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094ce8a29efa---60140064402.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/3760e561dddaf75ef6baea0801d696b7/4496385421.pdfIn PDF document text
    • http://cipetbhopal.com/webimg/files/dosuxivupusanew.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/d7658b70581bdc47924a32a94112b763/49785132339.pdfIn PDF document text
    • http://hebammenglueck.de/ckfinder/userfiles/files/17806177519.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160789cd2921a9---74282423790.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/zezofamanitop.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16094f7f368aab---lemumumut.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/59253927064.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160908b009d65e---wajulasivototu.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088f14f0f651---gibaviwuwagufabef.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/5315b5422ffca6398bf9fd4c33070fb7/27271443472.pdfIn PDF document text
    • http://cy2hand.com/userfiles/50415446793.pdfIn PDF document text
    • http://yavuzselimvakfi.org/resimler/site/files/64031322871.pdfIn PDF document text
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/9b8484b35037642733de20918d1819be/temosimiluzi.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160717c4f64f8e---81194784769.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aefc048504---lusad.pdfIn PDF document text
    • http://micruts.org/userfiles/file/ninoze.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/808417429c62d0c4f25c7d6983199727/bikil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=socket+head+cap+screw+dimensions+metric+pdfPDF 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_off00011fbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBE 19036 bytes
SHA-256: 0170dd6269356817d24d51d8d2129dab20df6895f3a1a374cff8a3a7cb58a6cd
font_01_sfnt_off00015246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15246 11092 bytes
SHA-256: 905b9f9436df6dcc258f3d0cff75552251a5deac4a460d6c4b554334829ac1c2
font_02_sfnt_off00016c0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16C0A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1