Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6a3537aa86614cf…

MALICIOUS

PDF

86.2 KB Created: 2021-08-04 12:06:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 5257d421c01a4c8282c5148ae70cb10c SHA-1: 522d3fd73fdf8585be8d9b17bad95ae8c07f86ad SHA-256: f6a3537aa86614cfcb7152b08fdaea5cdae02b55b233645020826b63aeedb1b5
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, containing numerous embedded URLs pointing to various websites, some of which are hosted on compromised CMS upload directories. This suggests an attempt to lure users to malicious sites for potential credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://agriturismocorteerbatici.it/userfiles/files/32382958262.pdf In PDF document text
    • https://qnzar.com/files/femoba.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/bo16dp98va3q1i03k4lvfbdc9e/39880412919.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ec9f29adf0a---pixuxuzefaxe.pdfIn PDF document text
    • http://mhinflatable.com/upload/file/53468078477.pdfIn PDF document text
    • https://tirthmobile.com/wp-content/plugins/super-forms/uploads/php/files/hj2q8bup63ajjk15mk3r8c6sgi/2956690093.pdfIn PDF document text
    • https://beldaoyun.com/calisma2/files/uploads/4424067541.pdfIn PDF document text
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles//files/pepikuvupegonosusovisi.pdfIn PDF document text
    • https://businessservicesuk.com/userfiles/file/niwiwafadelak.pdfIn PDF document text
    • https://www.azembay.com/wp-content/plugins/super-forms/uploads/php/files/4447vk20i5qdi64lf6ugdeh5mj/14572226583.pdfIn PDF document text
    • http://kassa.pl/userfiles/file/jozisesomubilepikaxabure.pdfIn PDF document text
    • https://sieompaysdebray.fr/lesiom/txt/imgadmin/file/57451642627.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/ditidorevugurewemitev.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/fitovuravizepidadate.pdfIn PDF document text
    • http://evevoyance.fr/adh/.-/file/69558155311.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160819ebabbc14---rinasesomarude.pdfIn PDF document text
    • https://xlspandoek.nl/userfiles/file/61706521988.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/42827394344.pdfIn PDF document text
    • http://soldresold.com/Shradhdha-Mehra/soldresold/final/ckeditorimage/files/jetoxomezuvizovine.pdfIn PDF document text
    • http://eske.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160805c6356109---83533129188.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=baidyanath+ayurvedic+medicine+price+list+pdfPDF 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_off0000e954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE954 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001016b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1016B 11100 bytes
SHA-256: 6cf97e4eeab9b73b733ed44c74be814689a26aeef8ae25d8f0b05e237550b67a
font_02_sfnt_off00011b23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B23 17900 bytes
SHA-256: 8c65163f781447b1deca3448e4f7b696a84531c346cd83f344f8ee8fd35ad5f0