Malicious PDF — malware analysis report

Static analysis result for SHA-256 33b3969805f917a3…

MALICIOUS

PDF

71.4 KB Created: 2021-09-28 17:01:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 05a499bb320b3308bfc4061899889f5f SHA-1: 110de4718e84683119096675b006259bf8fd04f9 SHA-256: 33b3969805f917a314ab1ef85c22354bdff5a6d43bd50a61570106659bd10ce8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to other PDF files hosted on various domains, indicating a link farm designed to distribute malicious content. Heuristics suggest it's a link farm on disposable hosting and potentially points to compromised CMS uploads. ClamAV detected it as Pdf.Phishing.Trojan, and ML classification strongly flagged it as malicious. No scripts were extracted, but the structure and URL patterns are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 http://lineshare.net/upload/files/20210923183405.pdf In PDF document text
    • https://bnovum.hu/downloads/70407182786.pdfIn PDF document text
    • http://xn--80aesyq.xn--p1acf/files/file/wiloratolepa.pdfIn PDF document text
    • https://viettincapital.vn/upload/files/58443045329.pdfIn PDF document text
    • http://izeninfo.net/admin/upload/files/26872443026.pdfIn PDF document text
    • http://sooam.com/files/fckeditor/file/341305410613f9198d4bda.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/tumarugezozawumofosijul.pdfIn PDF document text
    • http://thaimassagemodel.com/ckfinder/userfiles/files/17383116776.pdfIn PDF document text
    • http://kieryk.pl/img/userfiles/file/vamugu.pdfIn PDF document text
    • https://losungversorger.com/product/file/xaxorabivejaramevewixid.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/37424746784.pdfIn PDF document text
    • https://isuzuphonoi.com/data/dulieu/files/16984214689.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/zanutajajuvisaram.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/nujivovamufug.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/hddu1idode85i73she17se7op6/nezuna.pdfIn PDF document text
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/94056157397.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/r3of4c1g1sc96rttl0ibpsh9c3/dekufanitujunilavodaxaj.pdfIn PDF document text
    • http://www.facyt.com.ar/ckfinder/userfiles/files/36623218880.pdfIn PDF document text
    • http://broadviewlibrary.org/uploaded_bvlib/file/zutularujumexokikukimi.pdfIn PDF document text
    • https://yifff.se/userfiles/file/31736284133.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/wabuxolojoduxosa.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16131ae1a57214---38624523371.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=whatsapp+apk+aPDF 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_off0000b506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB506 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD18 17904 bytes
SHA-256: aad48056b055de576db841b877ea6797d9cd2f901e2a61cee70c884841ddcc4d
font_02_sfnt_off0000fa55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA55 9840 bytes
SHA-256: b96fb2722064d30ef9bfdf0e160206a697f9c2647e6567010ea30c79ff81f4e1