Malicious PDF — malware analysis report

Static analysis result for SHA-256 350bd56b2f5a1fdc…

MALICIOUS

PDF

80.2 KB Created: 2021-07-20 02:07:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e792975fb24d374907fb436e978d9762 SHA-1: 46d3556b20144a2af01c56ee600a10e006bfec37 SHA-256: 350bd56b2f5a1fdc24edcc03fa430cd6d22ecc0d1c03377ff3fde347944fcc6c
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external resources, many of which point to compromised CMS upload directories or disposable hosting. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to trick users into downloading further malware. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, suggesting a campaign to distribute malicious files via SEO poisoning and compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://cgl.lu/userfiles/files/46181943423.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d76d7cc13a---kufodufakekugidajojoveg.pdf
    • http://osmed.cz/app/webroot/files/files/pajezixiwow.pdf
    • https://www.isnb.co.uk/wp-content/plugins/super-forms/uploads/php/files/d5aa41b8dc93a5aadc28fc08cf97dbe6/64197978157.pdf
    • http://temple.mo/userfiles/file/76816010853.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/03b3d51d547577ef6e733118e461ba7e/rirenuboni.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160989a64353cc---tugamakekeguresokimupi.pdf
    • http://phuocthuan.vn/images/pic/file/bixepozesuxozaderize.pdf
    • https://warsztatgdynia.pl/app/webroot/media/files/goxosazodiwalodijudexedu.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160843922d0c94---raludaxiwekize.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/b00763c0c9fcc93bef97148bcd88c91c/makib.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160873b7a9a6dc---figutuxazirefelosijofadu.pdf
    • https://dodomacnosti.net/data/file/durosepinin.pdf
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/5354e37e55ec42b40b9ad9f7b158c344/zuderaverijudupive.pdf
    • https://cedarcreeksauce.com/wp-content/plugins/super-forms/uploads/php/files/5f9b45350db048a8da5f6314c22911f6/74615707124.pdf
    • http://yuanjen.com/ckfinder/userfiles/files/20901203323.pdf
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/lumulu.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160cb32230bd49---72304757585.pdf
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/1o6o8n0nilh5ee0lsvhbpsmdp1/jufub.pdf
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b06b2861d9e---numumamerapinenir.pdf
    • http://www.la-rocca.pl/app/webroot/files/files/33268715448.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=je+amapiano+sample+pack+download
    • 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_off0000d48f.bin
904f20c49fdcac5fef54c3f980937d2614a8fa7f53ac9aa6ba1f8f8c57124277
pdf-font-stream PDF embedded font (sfnt) at offset 0xD48F 10648 bytes
font_01_sfnt_off0000ecf1.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xECF1 16792 bytes
font_02_sfnt_off00010503.bin
fef27331a21979cb5087cafae9851923905ea6df92380a9f3b912c2fc0184811
pdf-font-stream PDF embedded font (sfnt) at offset 0x10503 17672 bytes