Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3a1d4223ccb1e80…

MALICIOUS

PDF

83.5 KB Created: 2021-09-23 03:25:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 043df648eddef2589c049615b9886755 SHA-1: 7e3baac1be3f2d7503c6b35990619c2588242b0f SHA-256: d3a1d4223ccb1e804ebbc23f019d155104eda5fbf18b74ecca677b9464ad627a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The PDF structure and embedded content are consistent with attempts to redirect users to malicious sites, potentially for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • 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://oniceh.ru/uplcv?utm_term=synchromesh+gearbox+working+principle PDF link annotation
    • http://j-club.eu/userfiles/file/59930060379.pdfIn PDF document text
    • http://dezis.ru/uploads/files/36982483665.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/21661298478.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/37962954663.pdfIn PDF document text
    • https://nilsahost.com/calisma2/files/uploads/6191555038.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc2e9f3d81---20989406317.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/pipaniwubakutomus.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109161909461358.pdfIn PDF document text
    • http://www.allatpatikapecs.hu/images/file/vozovufuxibugak.pdfIn PDF document text
    • https://denimder.org/resimler/files/95661419907.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/c0e9685b68e8a1c784cf300e64f02564/rudipi.pdfIn PDF document text
    • https://whatproperty.ng/ckfinder/userfiles/files/16491045476.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/fezarofidokibesi.pdfIn PDF document text
    • http://nktrading.qa/file/files/55510403632.pdfIn PDF document text
    • http://speakingaboutnetworking.com/ckfinder/userfiles/files/20437938686.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/xuziruveberani.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/30526803298.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/dc1dsfeeeql93p8lb7jmbs2b5q/60070110587.pdfIn PDF document text
    • http://wonderpanel.com/app/webroot/img/file/7809903709.pdfIn PDF document text
    • https://kingcom.edesign.fr/gr33/web/uploads/assets/file/5790160909.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161425d867e2e6---31807171012.pdfIn PDF document text
    • https://www.iimranchi.ac.in/ckfinder/uploads/userfiles/files/vujujomizunuxevikidometop.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/78957978618.pdfIn PDF document text
    • http://coquicart.com/ckeditor/ckfinder/core/connector/php/uploads/files/lirufuka.pdfIn PDF document text
    • https://insolite.lu/img/userfiles/files/65938070268.pdfIn PDF document text
    • https://adikketiga.com/contents/files/46542528147.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_off0000de81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE81 18060 bytes
SHA-256: 7c86ff3389cde0e8088b40ba6cb1e371167ce03bfecaedb8c83fa0ee8cd4c6e9
font_01_sfnt_off00010d6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12585 11332 bytes
SHA-256: 62c5784e91b33286b44c335c86efc6406d9ae3e0e5cdd86e8cacc8624f365667