Malicious PDF — malware analysis report

Static analysis result for SHA-256 16d9c033e6a27890…

MALICIOUS

PDF

76.4 KB Created: 2021-09-17 18:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1d3c38c3c2e0ce33b2e8ff0e135aa086 SHA-1: 61fa85b9a561ea7914022cb49da0ffcce6552fe6 SHA-256: 16d9c033e6a27890b91e0c32d968e20b4976e23ced3dfde69634cdc31fef09cc
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and link farms pointing to compromised websites, suggesting a phishing or malware distribution scheme. The presence of multiple compromised CMS upload links further supports this, as these are often abused to host malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://huntic.ru/uplcv?utm_term=i+like+your+cut+g+roblox+id PDF link annotation
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/qrbfru2haacto009ccbgegve20/91649791116.pdfIn PDF document text
    • http://neodermclinic.com/file_media/file_image/file/20547222648.pdfIn PDF document text
    • http://mudrkanuch.sk/editor_uploads/system/files/dokubazamelewovatamegeke.pdfIn PDF document text
    • http://escuelasfutbol8.com/docs/files/802604714.pdfIn PDF document text
    • http://saconsultancy.com/userfiles/file/29191412671.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/zofugibagijadivi.pdfIn PDF document text
    • http://homestationrealty.com/userfiles/files/23258746369.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///ratuxe.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/2541696242.pdfIn PDF document text
    • http://suachuadienlanhhoaphat.com/hinhanh_fckeditor/file/kezibenim.pdfIn PDF document text
    • https://sweetburden.com/upload/users/files/98353658464.pdfIn PDF document text
    • https://luatsubienhoa.com/upload/ck/files/45207615869.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/77330725199.pdfIn PDF document text
    • http://korvet-sp.ru/userfiles/file/ruladaberovorutamajux.pdfIn PDF document text
    • https://dwitunggaljaya.com/sitefiles/file/jubirejakixer.pdfIn PDF document text
    • https://tsegypt.com/file/46806188767.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136856326d78---jefejikigu.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16131db0dee917---41148248199.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/69144259438.pdfIn PDF document text
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/tegid.pdfIn PDF document text
    • http://okudshava.ru/userfiles/file/89761745576.pdfIn PDF document text
    • http://njchemland.com/upload/files/jukobivoganujakisuzawotub.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_off0000c462.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC462 10608 bytes
SHA-256: 6c42b2848a8dbf410f3d066ab50979f21fabeb44f618a6fd67b5db049990c3e9
font_01_sfnt_off0000dc90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC90 18380 bytes
SHA-256: f5eb1d58104864f15ad95c69e31b58e203dd1d7f06f222ec0f361fea41e7d41b
font_02_sfnt_off00010c57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C57 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1