Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f5143687bb07fe…

MALICIOUS

PDF

95.2 KB Created: 2021-08-01 01:43:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: a1cde7fb983aeb41c3001eb9dc7a399d SHA-1: b0bc7b04ca38359a0ea3d316a0b24a32179939e5 SHA-256: 83f5143687bb07fe482ca5fa2ae2ee88926a60a2e98a5d5f7370140b7cfc9dec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://crysiq.ru/uplcv?utm_term=cremas+recomendadas+para+la+piel+grasa PDF link annotation
    • https://kompaspt1.com/contents//files/96327052686.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/26740717068.pdfIn PDF document text
    • http://hndgyl.com/v15/Upload/file/2021717553146694.pdfIn PDF document text
    • http://hotelrealerimini.it/userfiles/files/jebipaxororezudotewesujet.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0bf2ad061---7914653331.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16081058c2823e---76362248213.pdfIn PDF document text
    • https://ideylia.fr/uploads/file/lutalafare.pdfIn PDF document text
    • http://jdhs77.com/clients/58520/File/7578534410.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160bcaca4d5ee9---sixapi.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/c687217a58b4c3dffe4493215a3ec8ed/jokowadakevego.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9cf4c98442770e2f3b85c1c9c9fe4118/32524905559.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5fe75ffde---96922534952.pdfIn PDF document text
    • https://kawanmto.net/contents//files/93556836481.pdfIn PDF document text
    • http://www.specemc.ru/upload/files/18145638438.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/xaminewamisikunabuwa.pdfIn PDF document text
    • http://westmoorclassof1965.com/clients/5/52/52ec68f2b927accf75267cb07bfcc891/File/gozubasa.pdfIn PDF document text
    • http://zamokugrofa.sk/admin/fckeditor/file/pobasibanizorigoj.pdfIn PDF document text
    • http://donghobaoan.com/uploads/files/10982025102.pdfIn PDF document text
    • https://hanyauntuktesting.com/contents//files/63902596875.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/vk01bvnuijuh01jcms58cab0vh/32842692574.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/35c7b3f9785c4d833e8a9b1318143bdf/pewamokali.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/632a453180476ef3fc1ea9c8221ebd59/ridelizip.pdfIn PDF document text
    • http://energo-winstal.pl/userfiles/file/46565207301.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/kinofagabetulolonoxi.pdfIn PDF document text
    • http://holycrossyouthministryasp.org/clients/f/fa/fa15eac34f6f8ef5a8ada011ffef1578/File/maxelalexajijek.pdfIn PDF document text
    • http://s292376414.onlinehome.fr/datas/imgmail/file/2778809601.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_off00010e32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E32 10792 bytes
SHA-256: 772ff3c16a6c481d98d783148f0c4cb95a2c4a5b13a85bafdb6efbe1c7f8e54f
font_01_sfnt_off000126c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126C4 18276 bytes
SHA-256: 04a0e11847d09406bbd8fe0f72216163bcc2ae18267a06030ce0848bdd7a66c9
font_02_sfnt_off00015553.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15553 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1