Malicious PDF — malware analysis report

Static analysis result for SHA-256 5666d2b57ee097c1…

MALICIOUS

PDF

82.3 KB Created: 2021-09-14 12:35:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 66c683273c7bf75a37c3743e20f2613b SHA-1: 3d11ddeed2cd1b1567c753651afd960945e96f2b SHA-256: 5666d2b57ee097c1b5f0d7411d445ad35cd9c1e8d1d3397ac0fbfd12e675c562
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The presence of numerous external URIs, link farms pointing to compromised CMS uploads, and a visual download button lure strongly suggest a phishing or malware distribution attempt. The ML classifier also returned a high probability of maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=temple+run+2+full+game PDF link annotation
    • https://sieuthimaycafe.vn/uploads/file/23983626391.pdfIn PDF document text
    • http://hurtglass.pl/upload/file/roribodixixabosafutozive.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/igrl84uatr7sgch4ghpjn35am0/vuralojaridelet.pdfIn PDF document text
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/b2hudggc05d1e2sstsh6vpbf0p/femerefalunuvojakedise.pdfIn PDF document text
    • https://bocion.com/ckfinder/userfiles/files/5812450756.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/730966465.pdfIn PDF document text
    • http://architettoannalisatinelli.it/userfiles/files/33667304794.pdfIn PDF document text
    • http://duepassidalcentro.it/userfiles/files/wudisutoxanifuw.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/gewodekus.pdfIn PDF document text
    • http://madang.eu/f_pds/fck/file/44436042192.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/64673937354.pdfIn PDF document text
    • http://geofer.eu/userfiles/files/6898658768.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/fkir8ohslgjoot4hcvhk665q87/40453898469.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/73819654550.pdfIn PDF document text
    • https://somogyplusz.hu/files/28561787262.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/4km6urmbg0oqsnei55usscg0ik/90299937166.pdfIn PDF document text
    • http://studiomanzetti.it/userfiles/files/69263278665.pdfIn PDF document text
    • http://palazzodiaz.com/userfiles/files/nazapowi.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/82527593548.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/7290953145.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210906165421.pdfIn PDF document text
    • http://wpchkg.com/upload/image/file/69354009567.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613863ad2d5f2---1296951265.pdfIn PDF document text
    • 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_off0000de04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE04 17920 bytes
SHA-256: 33d1c5f93cad0b7f6a55f201311b1308ca9d51c2ebd0a1ac523214d9ac1cf3f5
font_01_sfnt_off00010c00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C00 10408 bytes
SHA-256: d8f6a8d06b545bee074c0a610b576d8f50b61744ce5abb2556313b700a302133
font_02_sfnt_off00012393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12393 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1