Malicious PDF — malware analysis report

Static analysis result for SHA-256 b73bb7e882aedf4d…

MALICIOUS

PDF

87.0 KB Created: 2021-06-29 21:52:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 428d1f154f2d82894dbc28510aeddd06 SHA-1: 4fabfe3008070181db8736be6c4ec5753f4e0da3 SHA-256: b73bb7e882aedf4d6fb06f27a351ad1abd4db1a0fbcdd6860180c4976f064691
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a significant number of URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript may be used to facilitate redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://ienter.bg/files/tikaguxagike.pdf
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/40569163431.pdf
    • http://staresecurity.com/userfiles/file/86222143249.pdf
    • https://geneticapanama.com/userfiles/file/kabisimozavaninotu.pdf
    • http://www.pilonidalsinus.gen.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16071cf315bcda---21628713714.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160753369ddd18---35761552394.pdf
    • https://go2germany.ru/files/file/wolaxesufotakal.pdf
    • http://stressmanagement-karriere.de/userfiles/file/mujijeximugekagukud.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160702e93a7b4b---76658634781.pdf
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/fekut.pdf
    • https://artasedanasingaraja.com/uploadfck/file/61248091073.pdf
    • http://jaika.in/images/documents/files/titebinezojol.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097f9571adaf---43190592228.pdf
    • http://cuatudongsaigon.vn/uploads/files/56763153271.pdf
    • https://okna-stv.ru/userfiles/files/webezujopuda.pdf
    • http://w3-japan.com/js/upload/files/sekemukutebep.pdf
    • https://bawwabatrizq.com/userfiles/file/31376352780.pdf
    • http://goteneplast.se/files/images/file/nalasomabupokanevo.pdf
    • http://alexhofford.com/temp/files/file/biripejagizireju.pdf
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/b1389997cb5137fe6ee2e7a8415054f5/18773772709.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcc0623c9e---76892985600.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fdac161e24---47886279386.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/16080593c72905---82794878158.pdf
    • http://exclusivelimoservice.com/ckfinder/userfiles/files/monevozizojeferibasarak.pdf
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/3cf93584c15060585605daa5bdd2a341/perujonunimed.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=mindfulness+and+burnout
    • 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_off0000eeb1.bin
5ad7f0708acfb8e33e1743f85d88b521b0898e831ec3a564e7d762cd3dfb8917
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB1 10580 bytes
font_01_sfnt_off000106f2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106F2 16792 bytes
font_02_sfnt_off00011f04.bin
c9fe4406e4d8f201696ef814964b2519106218a28b347e80a6ea4a6d7a8a9378
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F04 17720 bytes