Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbc803945bc25708…

MALICIOUS

PDF

92.4 KB Created: 2021-09-18 19:31:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 810964ef1925347d19df3756fa89babf SHA-1: 037b94b0428aae7d0dec20764c084e4d804458fb SHA-256: fbc803945bc2570869aaf78765483a0f8fcbef22c0e758188ac479ee08e3827c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated, preventing a clear understanding of its direct purpose, but the link farm nature and compromised hosting suggest it's used for phishing or distributing further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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://dxqzx.com/ckfinder/userfiles/files/20210905_095156.pdf In PDF document text
    • https://jecoexports.com/ckfinder/userfiles/files/tufivefafujolaliki.pdfIn PDF document text
    • https://flardochform.se/userfiles/file/15667168588.pdfIn PDF document text
    • http://tyextractor.com/d/files/vimetepizuwobexetog.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210907101425.pdfIn PDF document text
    • https://gujaratisamajparis.org/upload/files/fajenumoxukede.pdfIn PDF document text
    • http://inarchengineering.it/userfiles/files/gexujenetamamovujinituk.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/gipilimonivefafokogi.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16141fd4de73a9---suwiwawexo.pdfIn PDF document text
    • http://szguilong.com/userfiles/files/85657383198.pdfIn PDF document text
    • http://villacappuccina.com/userfiles/files/33435870206.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/0ee07d1444a4ab3b80e59652d63261c4/85452617030.pdfIn PDF document text
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614281062a281---xuwabozilaxibiwu.pdfIn PDF document text
    • http://thelifelesson.net/home/tappingchanges/public_html/dowalumniusa/ckfinder/userfiles/files/65623925834.pdfIn PDF document text
    • http://kechengchem.com/upload/files/wajukoxatutojadetope.pdfIn PDF document text
    • http://sfalojistik.com/userfiles/file/97904524463.pdfIn PDF document text
    • http://thucancakoihikari.com/luutru/files/70777355759.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/vumibugakaledanajewo.pdfIn PDF document text
    • https://manpowernepal.net/ckfinder/userfiles/files/48397076993.pdfIn PDF document text
    • https://bk.knu.ac.kr/ckfinder/userfiles/files/gusumesonalowilomawi.pdfIn PDF document text
    • https://ebooksweb.net/files/file/71967179171.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/161373fd7974b1---gebenem.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/73765547723.pdfIn PDF document text
    • http://aokunoil.com/ckfinder/userfiles/files/64597791149.pdfIn PDF document text
    • http://happyorderfood.com/uploads/files/90633283085.pdfIn PDF document text
    • https://tolgyesvolgy.hu/userfiles/file/bakinor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=the+doppler+equationPDF 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_off000104a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A4 18140 bytes
SHA-256: 8cf186479637405344f469215fd0667881cf962a3d7d569b179918acbe476a48
font_01_sfnt_off00013410.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13410 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014c27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C27 10532 bytes
SHA-256: ff735033ed9078f31f7ec439b94d67c0ccc8036a46c60622d18388c06975265e