Malicious PDF — malware analysis report

Static analysis result for SHA-256 41122e83e61912f5…

MALICIOUS

PDF

79.1 KB Created: 2021-09-09 12:55:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c33c458c3b662730612511f62d23307 SHA-1: ba133fc75df36e859c39d61fb35dbb8003e031f7 SHA-256: 41122e83e61912f5ee16cc72f33f205494435dd0ed69a8595a64f77c2a1c6bc5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs that point to various domains, many of which are hosted on compromised WordPress sites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a small PDF acting as a link farm, suggesting an attempt to direct users to external, potentially malicious, websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://inwebjor.ru/uplcv?utm_term=phone+hdmi+alt+mode
    • http://kulturazebrak.cz/userfiles/karivenutipifodok.pdf
    • http://3bbb.fr/ckeditor/upload/files/1986939103.pdf
    • http://euro-ex.com/images/blog/file/44110956997.pdf
    • http://thegioimercedes.com/upload/files/80463525374.pdf
    • http://besttailor.info/ckfinder/userfiles/files/89762902528.pdf
    • http://captainkillmite.com/uploads/files/202109070128009828.pdf
    • http://permanentnimakeup-brno.cz/userfiles/files/91805401157.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612ed71317312---vixodawevur.pdf
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613534e62d0bf---63940651950.pdf
    • http://cpk.by/ckfinder/userfiles/files/vazajozoxexiwetazafi.pdf
    • https://ibexquimica.com.br/ckfinder/userfiles/files/fetofebedor.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16136ba74b619e---74528033042.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/2kh7p96nvioqnm62s2c4sfigc7/nofuvezemozalor.pdf
    • https://leresto-niort.fr/images/userfiles/files/55201978692.pdf
    • http://sklenicky-obchod.cz/web/admin/fckeditor/userfiles/file/99761638386.pdf
    • http://ankurgroups.com/userfiles/file/19630699732.pdf
    • https://harshahometutors.com/uniformkontakt/userfiles/image/files/58213334726.pdf
    • https://makenie.com/upload/files/544045080.pdf
    • https://millersexpress.com/userfiles/file/45178832643.pdf
    • http://birnagarcollege.in/userfiles/file/71292481893.pdf
    • http://headlinesdinerla.com/uploads/files/wuwitifixaramufavex.pdf
    • http://fatename.com/uploads/files/202109010554094763.pdf
    • http://nuestratierrapremios.com/campannas/file/48015401613.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_off0000d2c6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2C6 16792 bytes
font_01_sfnt_off0000ead8.bin
10d10a66d64e4569c9105233996a58d8fb0b00be109a7c547f91289bafab740e
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD8 17552 bytes
font_02_sfnt_off00011876.bin
3262f7c37a1adfe4a06972ce16846e5b16f899422ca3defe6966dcd1cb5a54e7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11876 10244 bytes