Malicious PDF — malware analysis report

Static analysis result for SHA-256 c87dcbab0ac7dbd1…

MALICIOUS

PDF

81.8 KB Created: 2021-09-22 09:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 90081b15c0c98626cf2f7b475334b30e SHA-1: 5fdc344d7537a050b39bdc6c2b4b6b47221b8c92 SHA-256: c87dcbab0ac7dbd119bb4d940947452816b416993be6d39a1ce907d50323cf35
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to compromised WordPress uploads and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document, potentially leveraging embedded JavaScript for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://huntic.ru/uplcv?utm_term=email+widget+android PDF link annotation
    • http://qualityfirstservices.pro/testingsites/advantage_aviation/assets/media/file/digasudilesepigiloroz.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/161486c135d42a---48129037333.pdfIn PDF document text
    • https://resicolor.com/upload/files/71545733449.pdfIn PDF document text
    • http://irina-beha.com/ckfinder/userfiles/files/kifatarekozawudepigu.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/27055697494.pdfIn PDF document text
    • http://pokemom2.com/uploads/files/nelikezamewufuxe.pdfIn PDF document text
    • https://lwim-ouargla.dz/ar/files/73657562219.pdfIn PDF document text
    • https://songiadahoaian.com/upload/ck/files/jemazoverabalerijojuxaze.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16135cc53a2741---6665279341.pdfIn PDF document text
    • http://dylogistics.com/userData/board/file/43828656218.pdfIn PDF document text
    • http://for-rent-antwerp.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613feeae578fc---natasufonirawenizesaju.pdfIn PDF document text
    • http://controlsystemco.com/cache/fck_files/file/miwukidekepufudabujujujav.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/nizefomoluzeji.pdfIn PDF document text
    • http://24cvety.ru/upload/files/fewutorogetarajatopopubi.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1e9959a5c---rutofabixenakilepeputege.pdfIn PDF document text
    • https://xn--fiqa735be48e.com/upload/files/90410001812.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/pagitojiwefezukejamot.pdfIn PDF document text
    • https://buyafranchise.org/files/files/92334713823.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/77178990145.pdfIn PDF document text
    • https://sherwoodchamber.org/ckfinder/userfiles/files/89078523546.pdfIn PDF document text
    • https://loyallcanada.com/editor_files/file/80278448744.pdfIn PDF document text
    • http://clainvest.pl/userfiles/file/badurizewop.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7f00be715---nezip.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/26043156525.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_off0000dbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE6 17992 bytes
SHA-256: c60cf3745878a85f3766e59e91711fb947be4154805318b51d3177943eadc8ef
font_01_sfnt_off00010a03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A03 10492 bytes
SHA-256: 3f12fb1801c07ee105c8584c824486f84b4e20511ecfd7a41840d2c1a3d7e88f
font_02_sfnt_off000121a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1