Malicious PDF — malware analysis report

Static analysis result for SHA-256 33a738d01187c283…

MALICIOUS

PDF

88.4 KB Created: 2021-09-02 18:17:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 32367e11df2a65f639973a5db59e2292 SHA-1: a92594051cd262a0d62b9d5b05757497285c0bad SHA-256: 33a738d01187c2836833128f3cf5797bff64ff71be04050a8b443dcebb7876fd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The primary function appears to be acting as a link farm to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://korea-seals.com/ckfinder/userfiles/files/43915481759.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/885c76458bbbd6ec5042afe1434d8843/44616261093.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/6219aedcc76d45afffe4a9c1bdee5b39/tejuxilokibadu.pdf
    • http://fijiembajak.com/uploads/ck_uploads/files/sasenivenir.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078bdc96046f---zugokakusikir.pdf
    • http://ekotop.eu/userfiles/file/ximexetulaferusalatuk.pdf
    • http://france-ex.com/images/blog//file/4050978748.pdf
    • http://banglatalkies.com/dynamic-images/cms/file/27967294282.pdf
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/gumoxep.pdf
    • https://sweetburden.com/upload/users/files/nulodezoxolubarizebidakol.pdf
    • https://syntellect.ru/Repository/file/35644525787.pdf
    • https://truck-diagnostic.ru/wp-content/plugins/super-forms/uploads/php/files/7a9a094d8b6dfc750b739dca12525703/89034641760.pdf
    • https://wipaphun.com/UserFiles/File/93616374279.pdf
    • http://inoxbienhoa.com/upload/files/zomitim.pdf
    • http://www.amanuttarakhand.org/ckfinder/userfiles/files/73590911581.pdf
    • http://amon-syotengai.com/userfiles/file/37942128388.pdf
    • http://cukrarnakolbaba.eu/obrazky/files/gulemerevi.pdf
    • http://sun-apartments.pl/data/pages/nopubikobuwuzavixaf.pdf
    • http://sdhmladavozice.cz/userfiles/file/niwumuwopemado.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1609359f6befa3---xifisosi.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160f0ac50b3f9f---kofagewefe.pdf
    • http://ashioke.com/images/library/File/sisenobixep.pdf
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/i0mgdat1qdr9hgbgk46f27vrbn/tegegapojo.pdf
    • http://doggystylzgrooming.com/admin/photos/file/40935593573.pdf
    • https://www.blondel-bois.fr/ckfinder/userfiles/files/furixida.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=selling+on+ebay+for+dummies+pdf
    • 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_off0000f3b9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B9 16792 bytes
font_01_sfnt_off00010bcb.bin
3a3cbb647b0ea90101efdc63c66e6c99498d421cfa5f1ba56cc4fc22c55777a6
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BCB 17852 bytes
font_02_sfnt_off00013a6e.bin
b39c040131d2462cd23dc54433ac5c1eb884f5778f3eb5fe346f04ddcba9dacd
pdf-font-stream PDF embedded font (sfnt) at offset 0x13A6E 11172 bytes