Malicious PDF — malware analysis report

Static analysis result for SHA-256 43e23728266ebb08…

MALICIOUS

PDF

82.7 KB Created: 2021-09-02 10:15:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1694265d09bb5c9513f9a90bdf14009c SHA-1: a71e98c542f01861bdae4691041ecf9d5dcaba7f SHA-256: 43e23728266ebb08be4c776a1ef9ef34f22f54b6f6f479d69dd07a4805c0fd03
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the presence of external links and the nature of the heuristics point towards an attack pattern involving directing users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://synerhu.ru/uplcv?utm_term=funny+pumpkin+pictures PDF link annotation
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160c40a5795a6d---6396320138.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160888201c63d2---89381724910.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/64786744630.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095cc1359238---wedilonezefibaxuzewi.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/63335186554.pdfIn PDF document text
    • http://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/topijibosogigajiwaful.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/gopes.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/42a1972ade37b15a2e309b8d134393ec/24596308573.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160eda41ea7c4c---dezomupezexip.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/4324699273.pdfIn PDF document text
    • https://dakhoathienhoa.net/images/files/sowevakuvuxigoka.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afb42bb20a4---xanifu.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/bajimenedusatijerozit.pdfIn PDF document text
    • https://zbmbudomont.pl/userfiles/file/6185111634.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/lefitinipajupudisevi.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/c54b2e064ee5336548dd4e16b5198530/wozoxapejivese.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/62983785331.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bb09e6890b9---56061245933.pdfIn PDF document text
    • http://itkaufmann.com/images/fckimages/file/35706178360.pdfIn PDF document text
    • http://xatrbio.com/userfiles/file/59549987408.pdfIn PDF document text
    • http://zge-led.com/luodan/images/userfiles/file/94149794549.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/91992992401.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_off0000e160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE160 10488 bytes
SHA-256: 44bb7b57eb7bd1f8c293f6c760172c5f7a6aab9b9af71d70b1fe2cf1c6d0e606
font_01_sfnt_off0000f93e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93E 16420 bytes
SHA-256: 407b0b690897064889a6c53efb51bbb2b88baf54cac8dba09d414a9053f14bd4
font_02_sfnt_off00012402.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12402 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.