Malicious PDF — malware analysis report

Static analysis result for SHA-256 266b73019ee8f1de…

MALICIOUS

PDF

96.4 KB Created: 2021-09-22 11:28:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7e89a58a0012aeeba328db05e5900023 SHA-1: 9808684b39aa2bd32e4e44feb56868b6edf80ef3 SHA-256: 266b73019ee8f1def3ced7ee9fdb1f64082de923c198c5fb17788b19642296f5
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with multiple URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://vertracapital.com/uploads/files/jovewirozadewabiwos.pdf In PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145257ae061d---leloverosanilafewoso.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/84099263263.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/39301192290.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/7v87frt38vf8amojt83u2ddv96/44374757600.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae472a78ba---11950055095.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/rogexadememotejojamunobu.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/jevakopasetej.pdfIn PDF document text
    • http://profesniprukaz.cz/ckfinder/userfiles/files/60048439175.pdfIn PDF document text
    • https://kalimati.in/userfiles/file/mipere.pdfIn PDF document text
    • http://ain.proximeo.com/ckfinder/userfiles/files/7531511037.pdfIn PDF document text
    • https://mlmrockstars.com/ckfinder/userfiles/files/deliteril.pdfIn PDF document text
    • https://tessuno.com/upload/files/6139707c36389.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/9600634541.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/rijuf.pdfIn PDF document text
    • https://quote-supermarket.com/userfiles/file/leruwizufuzawakinin.pdfIn PDF document text
    • https://blsautomation.com/ckfinder/userfiles/files/purozatosi.pdfIn PDF document text
    • http://lumieretvie.com/userfiles/file/komeru.pdfIn PDF document text
    • https://nazragame.com/calisma2/files/uploads/49535359632.pdfIn PDF document text
    • http://permagnet.com/upload_files/file/2109040614316993117nmbi0.pdfIn PDF document text
    • http://yoron.net/up/files/ramezudiwanurokatexoxe.pdfIn PDF document text
    • https://buzascsaba.hu/userFiles/file/91012071012.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/bosuvadasosar.pdfIn PDF document text
    • https://escritacontabilidade.net/fotos/news/file/32165909528.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=astrophotography+stacking+androidPDF 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_off00011537.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11537 10800 bytes
SHA-256: 9348077bfdbaedb1e472aee5957dcf74f147d89f3589ccf142b7488d7d82178d
font_01_sfnt_off00012df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14606 17728 bytes
SHA-256: a38ab8f772d7f12ec00e04823ec71ff293958d2fff8475aaeae30e8a3f3c6d84