Malicious PDF — malware analysis report

Static analysis result for SHA-256 15dc813830c13071…

MALICIOUS

PDF

84.7 KB Created: 2021-06-26 00:42:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9f9c6569aaab7f4bde83b1b2c368e3b SHA-1: 9822ecceb24bf7d6a3d36bff9bc5ef2874d1d942 SHA-256: 15dc813830c1307131582518ed80f680291d0a42912c49ac2159e7d89ab3bd03
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. This pattern is commonly used to obscure the ultimate destination and distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://brickchamber.com/ckfinder/userfiles/files/60408038812.pdf
    • https://cometsecurity.in/admin/userfiles/file/vasojisavaku.pdf
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/89700386410.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ac9aca5072---21810705906.pdf
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16090c71967d9d---dizevo.pdf
    • http://www.cuadernos.in/wp-content/plugins/formcraft/file-upload/server/content/files/16075e76ea2b89---90446607036.pdf
    • http://armanetti.com/images/fufuwaxukobawemafelen.pdf
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9bac2b1e8---kozefajesofapixutaveb.pdf
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/9e79100c756b475a6cc4f72070ec140f/sigudatanesetoresodomot.pdf
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a1f558c4456---danaxovozivaxes.pdf
    • https://aterhesseg.com/up_image/file/30016045843.pdf
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/8b7ce10606403600cb657fc2f98d0934/52213670946.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac82956337c---nijagudinosoj.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/df7887aece0b8cbea9c152dcdad678e4/55650843465.pdf
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/95942ls18jrca18d8kombekviv/xubisogujojukemapur.pdf
    • https://drvishweshwari.in/userfiles/file/watiguzewe.pdf
    • http://goergenpainting.com/clients/0/0d/0d1038892961fdbf96b6a8e7e8daca8f/File/26540829955.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a61a12edf2---gebenabizixowowemuriruxek.pdf
    • http://odpadykj.cz/UserFiles/File/pavexovawalosu.pdf
    • http://goraku-sangyo.com/userfiles/file/namumuxij.pdf
    • http://jaatkinson.com/userimages/gilewu.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5f9da7f7f---farijarusodexatezogam.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160be714266bfe---85513018199.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=track+teams+for+12+year+olds+near+me
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e79c.bin
c90678f689df47916354dc5efcde1068c406b7fde5baa6c9536bb2d78ce6931e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE79C 16988 bytes
font_01_sfnt_off00011407.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11407 16792 bytes
font_02_sfnt_off00012c1e.bin
95180ee283db9810025554d56dda4a71cd1338fd2e129000d041cba47e2fa0c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C1E 10884 bytes