Malicious PDF — malware analysis report

Static analysis result for SHA-256 deb310544663b004…

MALICIOUS

PDF

78.1 KB Created: 2021-09-20 06:20:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f52a873f3cc88a549047a0a4c9563e5 SHA-1: 7e72027c29781429825614916feaa456d62980b4 SHA-256: deb310544663b0041a096d5bf02769dea05bd09612fd022133fdd5ff8dc5336b
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or serving a malicious payload via the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://kimsanghun.com/upload/userfiles/file/2021971522572532.pdf
    • http://dispensapertutti.com/userfiles/files/16467978972.pdf
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161369cd200e2a---654241986.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613db85f9a4b2---kutegawez.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/burefuripokadake.pdf
    • https://jackinthegym.com/uploads/files/202109011126261549.pdf
    • http://inwama4.vn/webroot/img/files/58626975449.pdf
    • https://imahima.xyz/js/ckfinder/userfiles/files/nifimilozimosedemutafe.pdf
    • http://blfimmobiliare.com/userfiles/files/78906617593.pdf
    • https://hr-serdahel.hu/images/file/zinoveko.pdf
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/38424658630.pdf
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16140c02b63f29---vedunu.pdf
    • https://bodzlomu.com/userfiles/file/77923515540.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/prmf9qms9resngjlug4mhmmnnj/52718006020.pdf
    • https://www.idd.no/ckfinder/userfiles/files/66752604309.pdf
    • http://xn--b1adrijbbb.xn--p1ai/upload_picture/sawufimiwuri.pdf
    • https://tele-video.ru/upload/files/dukatugunukosofuzejadajaf.pdf
    • http://rrbrentacars.com/files/others/joxopotimojep.pdf
    • https://serrechevalier-skifun.com/imagesfile/56349353863.pdf
    • http://trungtamsangloc.vn/uploads/ck_upload/files/90218513356.pdf
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301796b4ef4---83323941260.pdf
    • https://musikkursus.dk/userfiles/file/fozatixowozisadagame.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/9v0c9t2nluitnelrf1poo091mm/sasuwezede.pdf
    • http://easytravel63.ru/ckfinder/userfiles/files/nebolasoluwutilemezisa.pdf
    • http://okudshava.ru/userfiles/file/zurexivofogebik.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=new+season+of+boku+no+hero+academia
    • 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_off0000cb2b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB2B 16792 bytes
font_01_sfnt_off0000e342.bin
cdb0686f865600caae281087365f9c6c4a50b837468443e8f5e34a8c0e655854
pdf-font-stream PDF embedded font (sfnt) at offset 0xE342 10992 bytes
font_02_sfnt_off0000fcac.bin
a87b31a92648dfee6ee3665535cf0f9f893cc16d88541b0f87804a660f401b99
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCAC 17644 bytes