Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e3ff024aa5677e5…

MALICIOUS

PDF

84.5 KB Created: 2021-09-18 20:01:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d8fdc2732bc257eb51397705867f5d13 SHA-1: ded4065d9b4a111c0c451095f125d9eb2e9db910 SHA-256: 6e3ff024aa5677e52093d2db53378d1e282761630bdcda4bc1a5d846ed7a4adf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the nature of the URLs and the PDF structure suggest it may leverage embedded JavaScript for redirection or exploit.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://www.institutvzdelavani.cz/files/59553136457.pdf
    • http://wonderful-foods.net/userfiles/file/47997908521.pdf
    • https://sitycare.com/FCK-UserFiles/files/47550998670.pdf
    • https://iwistw.com/upload/files/tokodubelusodimojiwo.pdf
    • http://xn--9i1b14lzokxjcrti5um.com/upload/fckeditor/file/wimebofib.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613beec6e6fa5---miwesisipewirovokukuvom.pdf
    • http://dralituncer.net/userfiles/file/99770783933.pdf
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/maxazorowitovofubojiz.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/161402a048d884---9912607931.pdf
    • http://xinge168.com/uploads/files/20210913015055_880682.pdf
    • https://bacsionline.net/userfiles/file/75309977939.pdf
    • http://0225674989.kad.tw/kads/ckfinder/userfiles/files/81155287850.pdf
    • http://kaies.net/upfiles/210904220825546126n3ax50.pdf
    • http://hongphuc.vn/userfiles/file/13221749851.pdf
    • http://german-ex.com/images/blog/file/37441283018.pdf
    • http://tt-ural.su/admin/ckfinder/userfiles/files/43684010397.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/35a0f98b5d254741c2c8b897a7271ac7/41828180383.pdf
    • https://defi128.phpascal.com/userfiles/files/waxopaledajakazepobipe.pdf
    • https://myshalewell.com/userfiles/file/49316568980.pdf
    • http://psychanalyste-gard.fr/ckfinder/userfiles/files/94625194922.pdf
    • http://yousefmaktabi.com/ckfinder/userfiles/files/91707735379.pdf
    • http://bikaji.zohukum.com/ckfinder/userfiles/files/xowusupisifevural.pdf
    • http://thesnowmanicecream.com/ckfinder/userfiles/files/45147653386.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16133657bc1bb4---mubimipug.pdf
    • http://buyyoutubecomments.com/ci/userfiles/files/lavibikolupowulu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=anna+karenina+english+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3fb.bin
e11639021ae82bc81d66597892112dbefd7f2cb67f426bbebb6fc3c29591e729
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3FB 1840 bytes
font_01_sfnt_off0000dc9e.bin
78fa607940f0c4f1d26b2e188f211f75595894615297d4934d52f97487d55eef
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC9E 21640 bytes
font_02_sfnt_off000113ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x113EA 16792 bytes
font_03_sfnt_off00012c01.bin
d0a8d538caf821d9af9c70a9695b0cb8ccc0ae540182fb8e3858303fa99f9f0e
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C01 10632 bytes