Malicious PDF — malware analysis report

Static analysis result for SHA-256 655fb35a65471b72…

MALICIOUS

PDF

76.1 KB Created: 2021-07-14 09:19:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c4f2db95f48f69af897cd974b2ec71e2 SHA-1: 98a729a577607378585a7f2d78521d18f426aa5e SHA-256: 655fb35a65471b72bfbfbcba4350eac3677c6e5b885dec8936a429c4a8b74e3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to phishing or malware sites. Although no scripts were extracted, the presence of external URIs and the link farm structure strongly suggest a phishing or malware distribution vector, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://cructi.ru/uplcv?utm_term=contraindications+meaning+in+medicine
    • https://its-bulgaria.bg/files/file/13947393860.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/61e0d1e12866f843993ffca396980c09/11208100457.pdf
    • http://inwallendorf.de/userfiles/file/62455669394.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16086e2580a5e9---17425788026.pdf
    • https://www.die-umzugsfabrik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8fac31c75---kasuxabujikabirilezib.pdf
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609082413c444---80635902851.pdf
    • http://thebranchoflife.org/clients/3/37/37a84c4c47f147f839b5d5a44bb1b86c/File/83748383843.pdf
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/590dd76e93bdfd0a172836f8b2d4f718/totazovapejawubuwup.pdf
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160a58c16350d9---dagoru.pdf
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/1149c4728cd89523ddacf59fa8956e24/60469481221.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160de3c66a71e8---76835315028.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b81ac18eec2---korabakavivusobabesidolo.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/16073bccc90ac8---xapodajulususix.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b0512968830---7768690224.pdf
    • https://aartipalette.com/userfiles/file/7497036378.pdf
    • http://vogiantinhmach.com/media/ftp/file/gasepusesoperemuba.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/c1a3ff57b63088cd82a6bd421da55e9b/40167331084.pdf
    • http://cricalliance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091ac072126e---92348469131.pdf
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/b34bb7467a483b0e708d3b3e4b49c39c/87084154236.pdf
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c67e30a5e83---vidavulow.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/ce72d0b97c861b0e45da2f98924198e6/98011431857.pdf
    • https://doi.org/10
    • 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_off0000c44e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC44E 16792 bytes
font_01_sfnt_off0000dc65.bin
31c03c7c69dafa97a93ed1e3142dcef1f82cea58beeffdf7bceece0aed6b6841
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC65 10696 bytes
font_02_sfnt_off0000f4bd.bin
8f4ce1f4157ff8b432e23951c8e8668235380ae6995d94de26524944dce937df
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4BD 17716 bytes