Malicious PDF — malware analysis report

Static analysis result for SHA-256 f643f7e5b8b7c333…

MALICIOUS

PDF

68.0 KB Created: 2021-09-29 09:29:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 865bb27a252350f4d02aa795771c8ac5 SHA-1: 771b3645fbf4e259d8005beb6524c9b5c7f3f09a SHA-256: f643f7e5b8b7c333a0571fd63bcc9294659b4789f73040f19e576658f992b13a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also features a link farm pointing to compromised WordPress upload storage, suggesting an attempt to host malicious files or redirect users to phishing sites. ClamAV detection and ML classification strongly indicate malicious intent, likely related to phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f05eb7e24d---vararumemamuwewik.pdf
    • http://dalnoboy.org/data/filestorage/upload/files/63987433802.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16141196bf368e---50325695201.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/161323f5e855f4---zuxezopivi.pdf
    • https://kligi.viart.lt/ckfinder/userfiles/files/92357341659.pdf
    • http://myappartement.de/web/editor/files/18182334291.pdf
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/wumasorupaxoraz.pdf
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/16857124295.pdf
    • http://pro-roubenky.cz/UserFiles/File/pubawiganelebove.pdf
    • https://happycondo.leaddeehub.com/userfiles/files/zinubanufidiwupoli.pdf
    • https://korankertas.com/contents/files/99728322158.pdf
    • https://www.hermanosvalerorecio.com/ckfinder/userfiles/files/nidiwanan.pdf
    • http://pokewaveanaheim.com/uploads/files/81382688440.pdf
    • http://apsencollege.org/test/fckeditor/file/4506195636.pdf
    • http://fusiongrup.ro/userfiles/file/bipefadefarukigoxojodi.pdf
    • https://kiaavcilar.com/upload/ckfinder/files/27962541513.pdf
    • http://pokeocncafe.com/uploads/files/24706644580.pdf
    • http://classiccar-jp.com/js/upload/files/pudawukidojilix.pdf
    • https://olgunbey.com/upload/ckfinder/files/suwixaxales.pdf
    • http://audyt.rowerowaszkola.pl/imgturysta/files/93089813487.pdf
    • http://ural-resyrs.ru/data/file/72887151920.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615400483391c---gogabi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=best+data+transfer+app+for+android+to+android
    • 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_off0000ad8d.bin
51e4e2ff0053c619d51cf43ab71847efd6c68fb4944ae706a68879ca94607c28
pdf-font-stream PDF embedded font (sfnt) at offset 0xAD8D 14608 bytes
font_01_sfnt_off0000d248.bin
3a3908e4d78cad72a8899e91e57d80f6cf286d2a83aeeed4eaa1502faf19850d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD248 10500 bytes
font_02_sfnt_off0000ea4f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA4F 16792 bytes