Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3ef923c5931d71b…

MALICIOUS

PDF

92.4 KB Created: 2021-07-31 13:13:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 61de5aa6043d78e280e6257c00e9633d SHA-1: 6f283b40a4ff0681cbfbc5483bdc17d3d78b6643 SHA-256: a3ef923c5931d71b2b544bff5a98ebb3e023f467e67e888975ac5c1214961167
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to compromised websites, many of which host PDF files. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic indicates the document likely instructs the user to open a password-protected archive, a common tactic to bypass security scans. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for delivering a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/04bd86a1020252bfd562ad3493afbd64/reridukogimatow.pdf In PDF document text
    • http://isagenixmakessense.com/ckfinder/userfiles/files/niwesomezoliguluzukufujat.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c20ed74760---lurodekotegexoxufoso.pdfIn PDF document text
    • https://mysmartedu.com/uploadimages/files/38799630165.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/tetat.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/mibukinavomufudijele.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/66110876304.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a1091a7da---45017206741.pdfIn PDF document text
    • http://romangruszecki.com/uploaded/file/35342916203.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/26c0091c47c7018d00e88ac85aba5e9e/widifominujipo.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/02aea66f1f0ac322a38a0a497bc92198/jowukaxekof.pdfIn PDF document text
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/sefaworinamanudivir.pdfIn PDF document text
    • http://myphamhelios.vn/luutru/files/zigugeguraxagikodikajav.pdfIn PDF document text
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e5991d7aa4---35238437647.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/603d3bf8e05a541202103b70103ddf89/74169116163.pdfIn PDF document text
    • https://jcmimoveis.com/userfiles/file/gibat.pdfIn PDF document text
    • http://faradbox.pl/files/file/19757409211.pdfIn PDF document text
    • http://accomplishtheimpossible.com/userfiles_ati/file/78965456238.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/62443596623.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088213f7b47c---gadamupumes.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a335a0fa97---84932443424.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c9ed31017e5---tabama.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072adb05dabd---80672813199.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=descargar+charlie+y+la+fabrica+de+chocolate+latino+hdPDF 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_off00010074.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10074 18676 bytes
SHA-256: a50e71f9b9dc3776d91d93d96387b56228f34bf3c4d4a6c4e856ef3054939d54
font_01_sfnt_off00013018.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13018 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001482f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1482F 11008 bytes
SHA-256: 4e06d66ef7306c1913322fa00315009fad572fd213ffdbc7da523dc2ebc60b08