Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b3da79dc3ccf6c7…

MALICIOUS

PDF

69.5 KB Created: 2021-09-27 19:18:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d918eee88de834a7f18de24379d3970 SHA-1: 27badd64883309d86773733a5b1e9f3e1c024268 SHA-256: 3b3da79dc3ccf6c7e99476a5c6e8061f6b9be933fc417e19cc695aa0666d922a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://irlanc.ru/uplcv?utm_term=game+online+ringan+untuk+hp+android
    • http://gkz-crimea.ru/userfiles/file/6266154173.pdf
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/13581952694.pdf
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614262d98354f---61824515229.pdf
    • https://ijaetis.org/ckfinder/userfiles/files/33096864586.pdf
    • http://villalapinetafavignana.it/userfiles/files/tijisizu.pdf
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161493e9821600---juxinigiliz.pdf
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/e033ea10d28135f911e8f23a4f0c03e1/70719216222.pdf
    • http://about-dogs.ru/upload/file/69778871419.pdf
    • https://leavereview.com/customerinterview/ckfinder/userfiles/files/40203517475.pdf
    • http://investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/17000523721.pdf
    • https://maurinet.com/userfiles/file/68259684983.pdf
    • http://glttek.com/userfiles/file/73753280919.pdf
    • http://zhongyuemedia.com/filespath/files/20210915202258.pdf
    • http://sten.kr/club/data/userfiles/file/20210926104640.pdf
    • http://csc-020.com/userfiles/file/20210903235434_7u8mcu.pdf
    • http://kalikraft.com/images/file/95135667664.pdf
    • http://hoangnamjsc.com/upload/files/63870563487.pdf
    • http://aven.su/userfiles/file/48485324426.pdf
    • http://rootbeadmill.com/upload_fck/file/2021-9-7/20210907140320554442.pdf
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144f47f70d3e---750143773.pdf
    • https://presstone.hu/userfiles/file/119597869.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1614ebc8042e38---sutaxon.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_off0000af11.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAF11 16792 bytes
font_01_sfnt_off0000c728.bin
e25652a1f909f4bbd81b3ab588ce8fae49409fcc210a1ee429211a64d86b223a
pdf-font-stream PDF embedded font (sfnt) at offset 0xC728 10904 bytes
font_02_sfnt_off0000dff0.bin
d0e050069b2c6619ae80c2a0146f71c7b3a1e21788b0ecb00439db06941f5f9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFF0 15172 bytes