Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b0bc9752215db30…

MALICIOUS

PDF

71.4 KB Created: 2021-09-01 10:19:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8b239998d17a8f02c63acdf3a5c5fcb7 SHA-1: 6828f30ac629d6f5e6211c1783fab75aa876af6b SHA-256: 5b0bc9752215db301ca7e94d23d7ea51208957198b6b47ee29ca4c8839faf550
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware hosting sites. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b62d3523f6---bepigizusurujebuwadikimu.pdf
    • https://tomas-music.com/contents//files/91973628403.pdf
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/433psp4rcg77ki463u058d783n/5941266361.pdf
    • http://cn-polylysine.com/d/files/55525395950.pdf
    • http://proxkimya.com/resimler/files/66542571459.pdf
    • https://www.gurgy.net/ckfinder/userfiles/files/75435326289.pdf
    • http://stressmanagement-karriere.de/userfiles/file/nodewobanewafejemepoguni.pdf
    • http://bannermaul.com/userData/board/file/zetab.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160e76003c0f5c---mafolefafololinip.pdf
    • http://helder-effect.nl/userfiles/file/5809232772.pdf
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/6d2q350utomkk3tqd7piupabuj/94345777172.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/317k4qi8ft1lb01cl72ncjvhbu/45945708214.pdf
    • http://mis.nrru.ac.th/gradjournal/ckfinder/userfiles/files/matetovetegokiwilupiw.pdf
    • https://getadoc.in/ckfinder/userfiles/files/luzedezar.pdf
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160abedf5d54c6---49821084506.pdf
    • https://sfasg.jp/js/ckfinder/userfiles/files/fulinusule.pdf
    • http://phillipwhiting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160daa63915666---pewatapawanawezib.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc46235b75---31034903941.pdf
    • http://drsuthichai.com/userfiles/files/josafetitudevidulak.pdf
    • http://asja-doll.ru/userfiles/file/90471309780.pdf
    • http://saipanbooking.com/FileData/ckfinder/files/20210829_9FA2F903F226340C.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=150+km+h+to+ms
    • 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_off0000b9c0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C0 16792 bytes
font_01_sfnt_off0000d1d2.bin
baf685415f80b105af2b97a5936400e06750ec26028c66fbdff1e3c2843cdd87
pdf-font-stream PDF embedded font (sfnt) at offset 0xD1D2 15712 bytes
font_02_sfnt_off0000f98f.bin
d8b6332f38108f18d89aef97ac29f7cbe48c719527cb9dd8282ffbb6631c683a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF98F 10040 bytes