Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f920b6b00c3817d…

MALICIOUS

PDF

88.5 KB Created: 2021-08-25 05:22:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6574dbb0875519bec6f017c285f7746f SHA-1: 6fd9d6397ce3b369105e0aba91b3f61b1efa31e0 SHA-256: 3f920b6b00c3817d7b2b40d537d001a6a27a9487c14e6d27d7ea9eb53e269dc9
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage, suggesting it's used to host or redirect to malicious content. The embedded URLs and the nature of the heuristics strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.northamericatalk.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e36c389bbbb---zezugijobonitavumefor.pdf In PDF document text
    • https://www.funes.gob.ar/ckfinder/userfiles/files/8177065660.pdfIn PDF document text
    • http://vatlieubaooncachnhiet.com/userfiles/file/palikonakufosunenaxij.pdfIn PDF document text
    • http://liveranigioielli.it/userfiles/files/52976784446.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/f87b253652cf53f3cd33ad6c113fd0ef/86675526345.pdfIn PDF document text
    • http://freetds.net/userfiles/file/37687905887.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/84449357084.pdfIn PDF document text
    • http://ontsgoi.shop/uploads/files/dopaju.pdfIn PDF document text
    • https://mumegram.com/userfiles/file/49455675849.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/62469249568.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/30116562831.pdfIn PDF document text
    • http://seamacros.com/upload/file/ganusif.pdfIn PDF document text
    • http://kutscher-customs.de/gfx/userfiles/files/jabed.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/a8a798517d3d43cce4a31a8eaf279eab/62804811482.pdfIn PDF document text
    • http://criollo-cocoa.com/userfiles/file/5415208316.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/iin77rcgla3nf74isodk269r6f/fikejavul.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/42478274328.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a791ff378fd---forawedejib.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/88712455134.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160785ca868a1c---kafunovokawuf.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/095468eb80d729265029ddddb84e257a/miketan.pdfIn PDF document text
    • http://minerva-collection.net/files/files/lonakebag.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/20167946812.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/8c3673a0ed2f80a57180cd107291f657/5463290931.pdfIn PDF document text
    • http://ferrogep99.hu/static/media/file/navefamoruji.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=types+of+pcr+techniquesPDF 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_off0000f76a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF76A 10692 bytes
SHA-256: b23f3fe3e77a999de7404fa08588bcaf6e2d8e343450e9f30efdb31ee5a4ef2e
font_01_sfnt_off00010ff2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FF2 17340 bytes
SHA-256: 25a7bf2a50c99e082c713993359debc2ccbb4c568079ac89bd3c5c2efd1afa24
font_02_sfnt_off00013cda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1