Malicious PDF — malware analysis report

Static analysis result for SHA-256 50da788785c25d5b…

MALICIOUS

PDF

72.1 KB Created: 2021-09-28 04:28:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2bcead23942aadc676f5f1582317f0e6 SHA-1: 36ab3dce42c4acce6894ba4eb172e3c79e974706 SHA-256: 50da788785c25d5b9b0ce7a3b50f78a688112ef87b0758901972abc899d5d64f
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 are part of a link farm hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The presence of JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://philabc.ru/uplcv?utm_term=watch+regular+show+online+free
    • http://myphammonly.com/luutru/files/13862889264.pdf
    • http://hzqzg.com/d/files/6599836692.pdf
    • http://elsped.hu/files/file/zesijopos.pdf
    • http://pazzo.jp/js/upload/files/kolegab.pdf
    • http://aztkgb.love-mrt.com/upload/files/38283550278.pdf
    • http://pro-group.ru/userfiles/file/zelomofire.pdf
    • https://maturana.cl/upload/file/bomufakoxukalagaxijobem.pdf
    • https://ubranni.com/uploader/files/javajeluremopedo.pdf
    • http://www.tobywells.org/media/fckdir/file/betidalojiziwoj.pdf
    • https://pearproperties.in/userfiles/file/viriwasixujodaluvuxulud.pdf
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/ad1dc4be5a450e895892edfeb5523dd8/28014732290.pdf
    • http://softtox.com/new/userfiles/file/gepofilakusamupawazapujal.pdf
    • http://balashixa.inhome360.ru/admin/ckfinder/userfiles/files/77987299780.pdf
    • http://skiflogistics.ru/userfiles/file/70597317370.pdf
    • https://lyna-garage.com/htdocs/cljr/data/files/vepijilodamepawa.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ff8226651d---telozulurili.pdf
    • http://ibrahimabuomira.com/ckeditor/ckfinder/userfiles/files/tiranorokokikireda.pdf
    • https://poganyvolgyi.hu/userfiles/file/tejenumefudafezog.pdf
    • http://cdseoulps.com/uploadfile/fckeditor/file/mimapi.pdf
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16141fe96e9d3c---14170780265.pdf
    • http://launensia.cz/ckfinder/userfiles/files/8041207040.pdf
    • https://12shio2.com/contents/files/kurilopejejo.pdf
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/b90ee894541807b6561825c6abcd7620/xewogaparabapaziserigi.pdf
    • https://casasholidays.com/scgtest/team-explore/uploads/files/76619401963.pdf
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/bdaa87af3efc62e533272e9433578ff8/furiret.pdf
    • http://iscelenie.info/files/file/moroxanin.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_off0000b69a.bin
fdf78b8ec68b2d4bff7984a9100d14d4b630f53f92cced12c9687b5ec8914740
pdf-font-stream PDF embedded font (sfnt) at offset 0xB69A 16744 bytes
font_01_sfnt_off0000e12e.bin
00cb730e1f5fb11a097abb285e6f8e17ee9a639982343f26b86aac0c8b7d5c7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xE12E 10796 bytes
font_02_sfnt_off0000fa1d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1D 16792 bytes