Malicious PDF — malware analysis report

Static analysis result for SHA-256 5641f63ec65b0bac…

MALICIOUS

PDF

96.4 KB Created: 2021-09-12 22:09:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 90847fa89e3e134dfce8769ca185a17d SHA-1: 5c2ab1130ec4243d6aaf322450b6e5ffdcfd8446 SHA-256: 5641f63ec65b0baca5105bf04ba8ede2e0f601cef7ddb0c79b28f744ed56988f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The PDF structure and link farm characteristics are consistent with attempts to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://xn--nmqu14inmf.com/upload/files/42830456028.pdf In PDF document text
    • http://jysfh.com/upload_fck/file/2021-9-1/20210901102335926286.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/tojotepezotulegegivagiguk.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/2795016527.pdfIn PDF document text
    • http://tjjjsh.com/uploads/files/20866080559.pdfIn PDF document text
    • https://transilvaniafishing.ro/app/webroot/files/userfiles/files/xavorafelodon.pdfIn PDF document text
    • http://gasthaus-steinkirchen.de/img/editor/file/zenida.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/55538532274.pdfIn PDF document text
    • http://shannonlakeestates.org/fck_images/file/namoliwu.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109130252119790.pdfIn PDF document text
    • http://kapsalonvogue.nl/files/file/zojugagulab.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210908152123.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613417ce65a39---35876100154.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/tikapuva.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133806c14bae---tuxifuginapudukulotuvif.pdfIn PDF document text
    • https://olivermilk.com/tctt/sites/aaa/file/13268530742.pdfIn PDF document text
    • https://easternresources.net/ckfinder/userfiles/files/44375894435.pdfIn PDF document text
    • http://njbeihang.com/uploadfile/file///2021090922415644.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/badifuje.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/1c0354cb925189461adaa5167b06a74b/30616647115.pdfIn PDF document text
    • https://mahanakhon.pacedev.com/ckupload/files/tonos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=introduction+to+quantum+mechanics+3rd+edition+solutionsPDF 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_off00011139.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11139 18808 bytes
SHA-256: 65d6b9b20b6e48321c76b2cd128135b45691590ca21caed02df7a87d00989e15
font_01_sfnt_off00014253.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14253 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015a6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15A6A 11004 bytes
SHA-256: cc314c4daaaaf8f77a9905eb17554f09335c2be7336eaa18056ab6858ef0e378