Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf3cdb4b87c01265…

MALICIOUS

PDF

104.1 KB Created: 2021-07-05 07:37:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5f0cffa546a2a9e10e685a4c63f1c387 SHA-1: 23abcfe9ebe1bd512fdc7014d293c9cdb83baf8c SHA-256: cf3cdb4b87c01265c16a09493bdc96f8b6a1bb89377c8f16aa3e75b6a92099f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

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://laborke.ru/uplcv?utm_term=what+do+cyanobacteria+use+for+energy+production
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c3ac45dc4b7---60623582099.pdf
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/b982f099e451951a2ce628734628f338/salosemasuxopirad.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcf64002ae---40882571152.pdf
    • http://angelojrobles.com/admin_initial_test/userfiles/file/vebugisamelebilowox.pdf
    • http://angarakshaksecurity.com/userfiles/file/xijokotixazob.pdf
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/b16d874277e2d6f2bf21378af31fad89/lolupoxobutimimux.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5bb3e2836---48835634529.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/1sfk0icssddggocp387nt7s5p9/19696516315.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada9c97deba---34690292193.pdf
    • https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/160989c85eae57---sajeve.pdf
    • http://bowlinggreenhsclassof66.com/clients/b/bd/bdf8ab256cd88a603fc2b95a051c5839/File/pajemugezirolekasabub.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608a4e10cffa9---91272371023.pdf
    • http://xn----8sbxab3abskk3a2j.xn--p1ai/media/file/mamurusumavaname.pdf
    • http://animationcoach.com/userfiles/file/51154488142.pdf
    • http://www.allatpatikapecs.hu/images/file/53345133831.pdf
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/4cc212af902405fa250fe46733d50568/rotezuvejidubunenel.pdf
    • http://dansensvenner.dk/imagesfile///91775974431.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/78062a49aceaeb7d57763e1f5c7eb938/87373374611.pdf
    • http://1959blackshirts.com/clients/866684/File/zuxagewexof.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/99326428501.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/95l2ih701700grr5jaiulnv447/xidomuwofug.pdf
    • http://www.apsetedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608074092a636---pokojabeveregidegovakutak.pdf
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/4abfc406c1b8047eba89e9ad4c64fa8c/59836173265.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000131d8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x131D8 16792 bytes
font_01_sfnt_off000149ea.bin
697895c65d9e41dd6451cc2ca0ca5a995e28a37b81569f7fd12e7b1161199faf
pdf-font-stream PDF embedded font (sfnt) at offset 0x149EA 18200 bytes
font_02_sfnt_off00017939.bin
8686bb45ae227b7a5fda7b2b6a62a1fd077c2c5951fd9d717b127ab9ec513eb1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17939 11200 bytes