Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c7b102c3e4de489…

MALICIOUS

PDF

75.9 KB Created: 2021-09-02 12:47:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 5b0017e03d9d858d6839b101806979f4 SHA-1: ff4ebd750fb33d26cac58760bbea458201566ef4 SHA-256: 3c7b102c3e4de48906bd4b90f6bb9ba29388afbe1d634b62c65ee38a8f716fde
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links pointing to compromised WordPress sites, acting as a link farm to distribute malicious files. The ML classifier strongly indicates maliciousness, and the presence of external URIs and compromised CMS upload links supports the attack pattern. No scripts were extracted, but the overall structure suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 5

  • 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://pistant.ru/uplcv?utm_term=english+for+academic+purposes+british+council+pdf PDF link annotation
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f34fbe326---95068321435.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0640552bb0---bejaji.pdfIn PDF document text
    • http://filatelianumismaticaumbra.it/userfiles/file/jugakavi.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16094e3e4da279---gikudozajal.pdfIn PDF document text
    • https://beldaoyun.com/calisma2/files/uploads/xilija.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/xewifekefemuvobowov.pdfIn PDF document text
    • http://veitali.com/upload/files/zezejorodoxagor.pdfIn PDF document text
    • http://bsp-plovdiv.org/ckfinder/userfiles/files/kurizemimajonisup.pdfIn PDF document text
    • https://ipssecurityconsultants.com/ckfinder/userfiles/files/lexajibokejipojanik.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/8718841764e0fd03dd965caf0b2af31b/fuxijiguvexibaxunumijiro.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607398591f8f9---juzokunatoka.pdfIn PDF document text
    • http://smlstripedbass.com/home/rock/public_html/ckfinder/userfiles/files/16564979313.pdfIn PDF document text
    • http://daming-school.com/userfiles/file/lirovab.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160734bfbedea6---64551309239.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/c4118e8e5911748729d357317567b4b3/xetaxu.pdfIn PDF document text
    • https://flvirginia.com/wp-content/plugins/super-forms/uploads/php/files/7b14b02dc14afcb0f852be1e6e9fe712/xidelitorakezuneruko.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf5496b22d---27184444778.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160841c72bf670---gepebapububipumeluv.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/4593140808.pdfIn PDF document text
    • http://runnersavezzano.it/public/userfiles/file/22120856625.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/63275996897.pdfIn PDF document text
    • 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_off0000c514.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC514 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2B 11288 bytes
SHA-256: c14209706ce1cb894e5a524d2205823d736097d80955adee353b299b5f59cd0a
font_02_sfnt_off0000f705.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF705 16488 bytes
SHA-256: 4ef9db26edf0ee81eead52bc11ff2711fa17d2f1f4dccf9035340bd95c55a5e1