Malicious PDF — malware analysis report

Static analysis result for SHA-256 e45db0597b83dfc5…

MALICIOUS

PDF

82.2 KB Created: 2021-09-12 18:15:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 86af190fa60c89de9586a88fc421a712 SHA-1: 74a1a260ed153a4d4475f526cf3935059b7346f8 SHA-256: e45db0597b83dfc52b71ac3c8ae8173a68a5a534d469c8cd2cebfa7adaed244d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm designed to obscure the ultimate destination. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM specifically indicates this structure. While no scripts were extracted, the presence of many unknown URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://cqhuaan.myhost360.cn/upload/files/09-03-23-24-30-36.pdf In PDF document text
    • https://semangkabiji.com/contents/files/fudawufozatazoxurixeba.pdfIn PDF document text
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/64733610323.pdfIn PDF document text
    • http://pitchdecor-construction.com/user_img/files/20160075564.pdfIn PDF document text
    • http://se-ty.ru/uploads/userfiles/file/xagedizusolawobev.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/35465328521.pdfIn PDF document text
    • https://www.acta-mobilier.fr/ckfinder/userfiles/files/75920280641.pdfIn PDF document text
    • https://dulsuc.cl/userfiles/file/97206127291.pdfIn PDF document text
    • https://felicityokolo.com/file/lujiwan.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/regodaxigarifavutesimup.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/39886754490.pdfIn PDF document text
    • http://zl369.net/userfiles/file/95744033226.pdfIn PDF document text
    • http://farmandari-sarvestan.ir/images/news/files/26962379693.pdfIn PDF document text
    • http://antonellascarpittadesigner.it/userfiles/files/mapevimajavago.pdfIn PDF document text
    • https://saksisan.com/upload/ckfinder/files/zilexegazotakufize.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/jetowasaruwulifime.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161303ab5a0e42---61022638791.pdfIn PDF document text
    • http://weiken-rc.com/upload/files/wudega.pdfIn PDF document text
    • http://budropol.de/Upload/file/wefesovizagi.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/junuwinunitumijejirej.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/5017263810.pdfIn PDF document text
    • http://naszymsladem.pl/upload/file/57420067961.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/64237695304.pdfIn PDF document text
    • https://wonkingchina.com/d/files/21105221161.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/91633333525.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=best+games+unblockedPDF 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_off0000dc5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC5B 10904 bytes
SHA-256: cdf6ca31a4aa70646ed0d27d15cbc3f8e04a3b10b67150a5d9fd0a5a6f566eb4
font_01_sfnt_off0000f578.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF578 17540 bytes
SHA-256: 106e83eb4e378e6f987f457f3ed7cfdab426f1246985f57d566175084cf2d65c
font_02_sfnt_off000122c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122C2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1