Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef0c924e7e3e7636…

MALICIOUS

PDF

75.7 KB Created: 2021-09-06 00:13:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a3a1423001a7c13f0f3c0a17b4120fd8 SHA-1: 5ca21ac9724a2426d7a3a31639224460a18f6336 SHA-256: ef0c924e7e3e76361da234d4de544a60d64ded7af7242e216be8c84a81d16aad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple domains, many of which are hosted on compromised CMS upload storage. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the structure and URL patterns are consistent with a malicious PDF designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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
  • 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://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/e45dc124f4d869253f73da5986b15785/55647708126.pdf In PDF document text
    • http://yuanhebiotech.com/upload/files/gikumavuv.pdfIn PDF document text
    • http://biometria.pl/photos_fck/file/pagunezakozu.pdfIn PDF document text
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081108296b9e---55270183517.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/cer44gpodmbmqns69d9cg1nvu6/79022171443.pdfIn PDF document text
    • https://oumkua.com/userfiles/file/lodoxanakuvekupijewekoj.pdfIn PDF document text
    • http://megalabsrl.it/userfiles/files/16088131305.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a402b28b2c---85536846433.pdfIn PDF document text
    • http://qianxi.cn/filespath/files/20210827183711.pdfIn PDF document text
    • https://buka.ru/sadm_files/taxukekafaledavufu.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/18499992190.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/24103203392.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/dosulofurowujutaj.pdfIn PDF document text
    • http://olimpic.hu/ckfinder/userfiles/files/73252354715.pdfIn PDF document text
    • http://iphysiology.ru/upload/lirotov.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/18605268321.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/ede0e130721f7eb2444cb431dd8f6c67/rufofokiturelujowuzigover.pdfIn PDF document text
    • https://valstybestarnyba.com/upckfinder/files/kobesenegutofajanaxewut.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/6dfe1d58fbac83c173a9503eded55dcb/nuduzaguxexekime.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/meumpc3ivq051950ngeo428fq0/13802058857.pdfIn PDF document text
    • https://servauto.fr/img/user/file/24607747145.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/5303fvvm3vm9kbcvic39djp3o2/nobejilukanupufotof.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/pko9fho2giiatnasanfcpuvjnh/88461354983.pdfIn PDF document text
    • http://coss-wynn-reunion.com/clients/d/db/dbe3622004495b304d8703879a486b7d/File/20721868523.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=call+upon+the+lord+lyrics+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_off0000c391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC391 10960 bytes
SHA-256: 2f9e164c3ae8466458bf5bfecbbbbd2071fda2cd96bee5aa310ed2028b3ce277
font_01_sfnt_off0000dcf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF8 17220 bytes
SHA-256: 10d65017f362de756e6d4e19e3f889c6f50e5425172c2dd633e4627c02495c51
font_02_sfnt_off00010938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10938 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1