Malicious PDF — malware analysis report

Static analysis result for SHA-256 21f3fcbc052ff5a8…

MALICIOUS

PDF

76.8 KB Created: 2021-09-09 17:56:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 4648c3981e742b7d654078796c3f8932 SHA-1: 454ba3ca547e41756c9d3d24ee4f7372b8918b48 SHA-256: 21f3fcbc052ff5a86242dff2586f0a3cdb5e795ab56ff690616a7f70ac66a68a
134 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 are hosted on disposable domains. 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 exploiting PDF vulnerabilities or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • 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://faceconnects.com/ci/userfiles/files/zefolegilukifafewidakov.pdf In PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/161334422717f1---30629381803.pdfIn PDF document text
    • http://arredamentoambienti.it/img/file/85786634024.pdfIn PDF document text
    • http://sumisaedu.com/FileData/ckfinder/files/20210902_2A7A3C50B68B3EE4.pdfIn PDF document text
    • http://xhzhengli.com/upload/32178463692.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/katasonorepomebavodabaluk.pdfIn PDF document text
    • https://harmony.im/userfiles/file/9288674604.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/35858881409.pdfIn PDF document text
    • http://geoplan.su/userfiles/file/geweja.pdfIn PDF document text
    • http://marktoby.com/akram/know_news/admin/userfiles/file/88399624566.pdfIn PDF document text
    • http://ibarugi.com/fckeditor/userfiles/file/juxeresomi.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/2433910616.pdfIn PDF document text
    • http://musclecar-taps.com/js/upload/files/zazomabewot.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/48152358950.pdfIn PDF document text
    • http://mstreatmentadvances.com/userfiles/files/2958339841.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/vazowexidejesupemizufiw.pdfIn PDF document text
    • http://mobilenmr.com/files/files/xozutobizikusufojizofeg.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/puvanuzewepi.pdfIn PDF document text
    • https://mahae.hu/files/files/99267279045.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/majixojikemuzagobewawaxur.pdfIn PDF document text
    • http://donghobaoan.com/uploads/files/69542753993.pdfIn PDF document text
    • https://uzmanwebci.com/calisma2/files/uploads/vegewikatukonisegumuweviz.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/41334723052.pdfIn PDF document text
    • http://precisao.org/files/files/liwagizire.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=10+free+insta+likesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB37 10256 bytes
SHA-256: 59fa20d71b5bec83c2d6c6ff011b01d457cd7e9d0a553df5342e95d1f0370f2e
font_01_sfnt_off0000e26f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE26F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA81 16920 bytes
SHA-256: 54e8f45698d7469b20b25f52b9e612ae10a4eabbe3b79f51486f15dc171aae50