Malicious PDF — malware analysis report

Static analysis result for SHA-256 959db955e8239f54…

MALICIOUS

PDF

83.0 KB Created: 2021-09-03 09:38:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ef0e7e85f7713c1f2d103fe54359815 SHA-1: d1a18da37482c7bf8541fd64326651f9d90ab16f SHA-256: 959db955e8239f54f878b29fac4bb7faa60440e2b4210d15950d1dfe33edb7d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous external links, many pointing to compromised or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. The heuristics indicate the PDF is structured as a link farm, with multiple distinct hosts and a high number of links, some using UTM parameters for tracking, further supporting a malicious redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://infiniti.e-library.tw/uploads/files/putugibuzuxebewev.pdf
    • http://blesk-stroy.ru/userfiles/files/85903392687.pdf
    • http://jshtextile.com/UserFiles/file///fuwomijet.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a977034195f.pdf
    • http://wooshin.kr/uploaded/file/16200083846102e93493d38.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098c84e071c2---4101132291.pdf
    • https://smartstone.ca/userfiles/files/23170690925.pdf
    • http://utuin.net/files/fckeditor/file/vakegawupogebepajom.pdf
    • https://eternalbliss.net/file/derov.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/715ab397f23bc2ee6ce4cd86c2d15c6b/77005216563.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609984918602f---74989195448.pdf
    • https://www.sevgiliyevideo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2d490cbbb---27660107919.pdf
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/160993da9e04ed---53830317620.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/aq33183apa9hnlfu82fsjf9gi8/pulukadutuvasixegex.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a210bba435a---fedeleviruf.pdf
    • https://powerliteaac.com/userfiles/file/jexodepitujubupodijitev.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d3ace63ec---badupipediweke.pdf
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/85834b609f822eda833640e3b5a4706d/30718219209.pdf
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af400e3afc0---40661635416.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160e922c56daa6---gorevadu.pdf
    • http://www.sphotobooth.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f9f983c84---13190931456.pdf
    • https://havanic.com/cache/fck_files/file/natawed.pdf
    • http://aygroupmuh.com/image/files/gaporavumeras.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=hamza+tzortzis+the+divine+reality+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_off0000dbf9.bin
3edfd4ed7fa0750e735fc1a6caf695e032b3ce61e62df4b84c054b3a5c6a23f5
pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF9 10996 bytes
font_01_sfnt_off0000f553.bin
a105c14aa79a1d5d32c573264500999736c62efd48535b0dd3295e61f59ab1b6
pdf-font-stream PDF embedded font (sfnt) at offset 0xF553 18888 bytes
font_02_sfnt_off0001269e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1269E 16792 bytes