Malicious PDF — malware analysis report

Static analysis result for SHA-256 5683739a426c783a…

MALICIOUS

PDF

70.7 KB Created: 2021-09-28 13:03:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 283f7e649083fdacf17ca4a9a6060f78 SHA-1: 7af982ea026d5e7dd53f0480b362ea5864db016d SHA-256: 5683739a426c783ae6d174570d3af97df969154567d8b2f4b29259a70cbe9311
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URLs, many of which point to compromised websites or link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 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 https://crewmak.ru/uplcv?utm_term=close+a+tab+chrome+shortcut
    • http://pusheng168.com/uploadfiles/20210916124215.pdf
    • http://cementfeet.com/userfiles/file/50224404057.pdf
    • http://jonme.net/ckupload/files/8161584445.pdf
    • https://parkettworld.com/upload/files/1523688661.pdf
    • https://ihotel2b.com/upfiles/editor/files/xetapiduxumatibosalojuge.pdf
    • https://oazapiekna.com/zdjecia/fck/file/zogedagiluzarujizaboki.pdf
    • http://fastbeatbattlerider.saint-fun.com/assets/upload/files/9427609876.pdf
    • http://teleinwestor.pl/userfiles/file/xoxoserex.pdf
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149c19dad31e---loxewadanawomenuledew.pdf
    • http://patriabrno.cz/userfiles/files/maroluzuzozomunogolunux.pdf
    • https://www.hemingway.bg/app/templates/js/ckfinder/userfiles/files/fufugivuxavoposifafaxo.pdf
    • http://studiospazioambiente.it/userfiles/files/13184980932.pdf
    • http://xn--49s538bo8ux8c.net/userfiles/file/revewilokidivixa.pdf
    • http://dermatologomiguelgallego.com/miguel/fck/file/vaxonagatomajofuguxigeme.pdf
    • https://brahmagnanam.org/fck_uploads/file/bokixuwoxo.pdf
    • http://yourmoneyyourbank.com/uploads/File/xanike.pdf
    • https://adsbudget.net/userfiles/file/vazoj.pdf
    • https://nguoixunghekiev.vn/userfiles/file/bemowinusalanuv.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/ppe9q36ud6qh1t71g335aqal53/favatowofavodifikalepivig.pdf
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614616cd2affc---23136182415.pdf
    • https://ntct.dz/ckfinder/userfiles/files/13393145794.pdf
    • https://embassyinvietnam.com/webroot/img/files/87941366780.pdf
    • http://serenetour.com/image/upload/File/64036711151.pdf
    • http://aiaato.com/FileData/ckfinder/files/20210924_ACAF16E7391D92FD.pdf
    • https://0900107678.com/upload/file/kazazabaxosetosodil.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_off0000b282.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB282 16792 bytes
font_01_sfnt_off0000ca94.bin
88d8cea557332b3a73cd51f9ee5a618b78be4fc5fed33daabce4f8834c996487
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA94 16752 bytes
font_02_sfnt_off0000f4e5.bin
29e278dbe990d0b3b0bddb412295fbc660f3158d24b621d5c6b93468a47b810d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E5 10568 bytes