Malicious PDF — malware analysis report

Static analysis result for SHA-256 591553b879498ccf…

MALICIOUS

PDF

79.2 KB Created: 2021-09-04 16:05:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 86934ed31cd291696cca80b9012f92b3 SHA-1: 1154cce34f6e9dc702ed3f01147ae007c2fab96c SHA-256: 591553b879498ccfb5e6c632b02f58064418310ef625912fc833c7337e2e1bf2
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV both flagged this file as malicious, indicating a phishing or malware distribution attempt. The primary attack pattern involves directing users to external, potentially malicious, links hosted on compromised websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://pr-jam.com/ckfinder/userfiles/files/bigodap.pdf In PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160813ec15bf56---bejilokafufusuvibawef.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/77c54266aec580efd5070705e123b8b4/6579441220.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/160f063ceeb9c9---xuloxunoxalafiwubufubo.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d4674da0df---26154657961.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/2a1itbd84nah76ic9ghp0rhsod/90372460205.pdfIn PDF document text
    • http://haphadoor.com/upload/files/rozomazarovarezevedojof.pdfIn PDF document text
    • https://mamotato.ro/userfiles/file/84140342362.pdfIn PDF document text
    • https://migger.dk/userimages/file/22665691752.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/34933276399.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/377ff1f38ad8c7b101e6ae0a813d4092/87027426661.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/46491692577.pdfIn PDF document text
    • https://miltonmattox.com/userfiles/file/50845009336.pdfIn PDF document text
    • https://iltuosarto.com/file/72306330495.pdfIn PDF document text
    • https://traveltokiev.com/wp-content/plugins/super-forms/uploads/php/files/l5bc4igdrm8cilqrd5usta5vl3/281881894.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/qmrinhhsvlc85sdvk2a6rvtvdv/ganobubasipa.pdfIn PDF document text
    • http://nuovojob.com/userfiles/files/53581612310.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160c3fa2b4e6a7---63037156287.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/68520936718.pdfIn PDF document text
    • https://duvanco.be/docs/files/87923271216.pdfIn PDF document text
    • http://thechelseaff.com/user_uploads/files/80666436941.pdfIn PDF document text
    • https://baongochoa.com/upload/file/wobato.pdfIn PDF document text
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/20eecb7f4d7c097da5791e784686bfc4/68136394094.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/pexinabavotikukur.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/buvabedurapemej.pdfIn PDF document text
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/5da41a583e8628af62e301125635c5c4/xavofekudojogenurimus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=manual+radio+chevrolet+aveo+2012PDF link annotation
    • 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_off0000cd15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD15 19168 bytes
SHA-256: b148e50b3043c31273c4efcf54fd053d7b3c3a59863b94a663e4258f8de82c8a
font_01_sfnt_off0000fea3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA3 10752 bytes
SHA-256: af3e7e25ba0f7ad94e961adf96b7660dd2133dff9059db33d5089d64a7aa94ec
font_02_sfnt_off0001175d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1175D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1