Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3727c54135ef523…

MALICIOUS

PDF

79.8 KB Created: 2021-09-04 03:51:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9f7430ed255b5bfd3ca71a7ea99828ee SHA-1: 62ca1bef3eaba228d32e0768f5268b9708c7056b SHA-256: c3727c54135ef523ebc45466cc656458e8c79bfb292f2241f595a65520f5beb1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to disposable hosting or compromised CMS upload storage, suggesting a link farm used for phishing or malware distribution. The presence of 'teacher's guide' in a URL parameter further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://zenkenmoshi.info/images/files/file/nepodofajevedebuzufev.pdf In PDF document text
    • http://alfavs.eu/userfiles/file/sorirekodajisi.pdfIn PDF document text
    • http://ibiforstarlight.org/clients/3/3c/3cfcca4e360ca8807b7dd7d6e7cbeae0/File/kewulasupisezezubiwazomoz.pdfIn PDF document text
    • https://ovalpolycoats.com/media/67157335227.pdfIn PDF document text
    • http://slsnn.ru/content/file/21076395382.pdfIn PDF document text
    • http://mariekevanvlierden.nl/survey/userfiles/files/minoxikajavokemuvere.pdfIn PDF document text
    • http://issaproject.com/app/views/panel/ckfinder/userfiles/files/97433545370.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/oqdft4h181dr10qv3l8ijfclvk/62466840703.pdfIn PDF document text
    • https://arichaindia.com/userfiles/file/48136111483.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/f176eff8948e11ad07331199cb84dcdc/30930043438.pdfIn PDF document text
    • https://fotokeramika.bg/userfiles/file/32817329095.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/418c746509baf8f8566670fc848ba793/31232222346.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/60801498877.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/6dddad7572816d7af38498d269360d93/golum.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9a85b3161---judefebo.pdfIn PDF document text
    • http://accessprecision.com/userfiles/file/wumobutujumame.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/65329793462.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1612d4ef628d62---mujubapebutefafi.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/22687577466.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/3krb4gfifb5ipoi9nl0rqqrn3b/vufipojebogotapobugum.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/51456364175.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607b63558c6e3---wevugepisugowosipazax.pdfIn PDF document text
    • http://zetrade.cz/userfiles/file/miralowogufalovozo.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/9614abef445628eba610af71aa485307/nanix.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/47959854350.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=teacher%27s+guide+in+english+grade+9+pdfPDF 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_off0000d1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9F1 10944 bytes
SHA-256: 17cef3b255e8f66ca18447894bfad0ccfb8ec5bc1d02b8e4c8ff0281c26aafaf
font_02_sfnt_off00010309.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10309 17820 bytes
SHA-256: 5a01d30edc6870476c963006ac2cec37ef5f0c659d8669e10ffde03d7a1fedb6