Malicious PDF — malware analysis report

Static analysis result for SHA-256 50cb381ec001bcc7…

MALICIOUS

PDF

80.6 KB Created: 2021-09-03 00:56:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7ec458aa520c12f4b1bc616927b90408 SHA-1: cdfbd8c147fc2d87515817c4613c477c041c6b92 SHA-256: 50cb381ec001bcc74127e44a3bbc003408cef16fc9c0283656b58f30e84c390d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains a link farm pointing to multiple compromised CMS upload directories, a common technique for hosting malicious content. ClamAV and ML classifiers strongly indicate maliciousness, and the structure suggests it's designed to lure users to external sites. The presence of numerous external URIs and compromised CMS links supports a phishing or redirection attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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.
  • 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://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608768e41a451---defepeja.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16070bd21ae4eb---xupibenafalamitisiromevo.pdf
    • http://baltic-rt.ru/ckfinder/userfiles/files/26206580709.pdf
    • http://hhsbluebirds1967.com/clients/b/b5/b592d679e9980e62d9d56be1bfb8b6b6/File/vufofivovegonizadudidam.pdf
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acdb55cbbbe---dafutexegaja.pdf
    • http://fly.no1-yes.com/userfiles/file/kakidije.pdf
    • https://igescanada.com/ckfinder/userfiles/files/wakibogekoviw.pdf
    • http://wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/80445511887.pdf
    • http://npi-management.org/ressource/site-image/files/wevobupasezobuximupuku.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607abeddc8d47---wujufoledamaxem.pdf
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/8827f80123472ad187bf985b3c3a064a/tezaraj.pdf
    • http://sugarfree-gelato.com/upload/file/meparexigozaj.pdf
    • https://peintures-descours.fr/fichier/files/96919479050.pdf
    • http://kidsjeodo.com/images/files/nidinejukumix.pdf
    • http://www.prieteniitehnicii.ro/documente/file/67160467207.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/9bc4dd552ad41b6dbd66e919e85e9137/wopajeposebebozavojakenu.pdf
    • https://icoachyou.biz/images/ckeditor/files/xufulapudo.pdf
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/16086a4385efdf---57211541498.pdf
    • http://dienmattroigiatot.com/uploads/files/47268931894.pdf
    • http://ahcxdq.com/uploads/file/280726236278.pdf
    • http://4x4autok.hu/userfiles/files/97506509231.pdf
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/d451b27b8c762d53938e2476a5e6dd68/ravijiwuveteme.pdf
    • https://101doctor.com/uploads/ckfiles/files/60b3d358a4879.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=organic+functional+groups+list+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_off0000d9da.bin
4cc4b382a1dbd82885f8cf2d34af7df0d235b87bee48969eab0a0070ab768ea1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9DA 10788 bytes
font_01_sfnt_off0000f2a4.bin
4ed9dcf06019a451638a9b870db1a446e61f5f6656f75a681bc5c443f8040390
pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A4 16564 bytes
font_02_sfnt_off00011c9c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C9C 16792 bytes