Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f1592a4545af410…

MALICIOUS

PDF

81.4 KB Created: 2021-09-19 06:53:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 38bdb5149204661cdf4cd2ca4ffb0688 SHA-1: ab6a534ffec6899157eafc3e88b8e97a62f95cef SHA-256: 5f1592a4545af410007ea3c71b421a1e7f874f94fcf1ff4021ab883c6ee80a48
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://smidgel.ru/uplcv?utm_term=words+that+start+with+long+e+sound PDF link annotation
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16135958e033d0---30483023313.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b90400b223---xazunanijexegezov.pdfIn PDF document text
    • http://digjamaica.com/app/webroot/files/96583740799.pdfIn PDF document text
    • http://cgemfoco.com.br/ckfinder/userfiles/files/87216526241.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/16142b1cc22b67---67222888720.pdfIn PDF document text
    • http://www.gc-antey.ru/ckfinder/userfiles/files/32990028630.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/55a986a35966356a4e4254291fd241bc/89802527997.pdfIn PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/kuniwixad.pdfIn PDF document text
    • http://techniq.ae/admin/uploadfiles/file/keravulad.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/wumazubu.pdfIn PDF document text
    • http://8njl.com/userfiles/files/fizaxasufojotilid.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/tusekagizafudav.pdfIn PDF document text
    • http://bubb.cn/up_file/file/memamirix.pdfIn PDF document text
    • https://www.confirmedtour.com/files/67072469470.pdfIn PDF document text
    • http://artc-polymers.com/upload/images/files/jikuluwosemol.pdfIn PDF document text
    • https://tpijobportal.com/ckeditor/ckfinder/userfiles/files/sapaxosikemokib.pdfIn PDF document text
    • http://fst-uinsu.net/userfiles/files/70209851384.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/mebojutezigikogurusuzivug.pdfIn PDF document text
    • https://maxlinder.com/admin/assets/ckfinder/userfiles/files/97364135951.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/fenazunamuvaserote.pdfIn PDF document text
    • http://ledspectrumthai.com/ckfinder/userfiles/files/70900337511.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_off0000d5af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5AF 19300 bytes
SHA-256: ffde9c98b66c90401dce8fa9b9bf7565a3e6fddaa50db7018dcfb3bfe7db2116
font_01_sfnt_off00010814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10814 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001202b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1202B 10704 bytes
SHA-256: ac5e54da9f12d6eedf6c898496c769fd85a68bfab832f8afb86c3aaad4a66b84