Malicious PDF — malware analysis report

Static analysis result for SHA-256 598d4b7aa9e8249b…

MALICIOUS

PDF

91.8 KB Created: 2021-07-13 18:36:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: fc3140efcce79a265a666ab1449f1037 SHA-1: 26b37201200fa5ffd0590ea8b72c1b5678c41038 SHA-256: 598d4b7aa9e8249bd917663180e2f7ed38181d9838f2680fcf814af2e507bd31
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack by hosting external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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 http://poorclarescork.ie/images/tonaledira.pdf In PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa2266a256---10527285481.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/re7ifpt28hhfg22r3tup9fgsj7/juwevane.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/7e96902e86f4eb3f7ff0ed52bda44dda/fesixiguwetefogifexepig.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a70448093---zowerirojedigebap.pdfIn PDF document text
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983fd4087f8---wedaregix.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/a79983c9f515667bbfed5201ef30df51/bepegonuz.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609176c808a70---43103200127.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/gosixodobuzulidokemava.pdfIn PDF document text
    • http://tuanayapim.com/rsm/files/66262903867.pdfIn PDF document text
    • http://oikoscoccatoarchitettura.com/userfiles/files/gaxirutelefuwunabumaxefe.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/d0d80634907459560eceb5cc3170323c/28674802485.pdfIn PDF document text
    • http://manixcnc.com/ckupload/files/titubowamazapulepeki.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/c0b8bd40ad24763bfb980208060122a1/92491032672.pdfIn PDF document text
    • https://vieclamxaydung24h.com/upload/files/rorumob.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/kj9d6o2r04jcsgm8hob3mv2a24/97069576588.pdfIn PDF document text
    • http://merwepizza.com/upload/file/60840942202.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/visogolibe.pdfIn PDF document text
    • http://irishvaughans.com/clients/7/7c/7cfe0b8ff6d5e3136a6575a9b258a09c/File/69264849045.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160cac62997a34---fujilomukaxut.pdfIn PDF document text
    • http://shsalumniauditorium.org/clients/f/fa/fa32e32112b7cad64a7d7e78b95ed61b/File/xugiwire.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/46087896580.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/87191339461.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/59h4ekm9veq9jkidsudt4lspse/baxidamegexomidis.pdfIn PDF document text
    • http://on-video.com/movies/movie_data/file/79197821837.pdfIn PDF document text
    • http://www.biotanika.pl/upload/file/pexeset.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=words+to+blinded+by+the+light+meaningPDF 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_off00010534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10534 17076 bytes
SHA-256: 9bc649ee1fba17e583ff0ecc658b9274248b968c7ac8f830e986d74059ad43f4
font_01_sfnt_off0001317d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1317D 10944 bytes
SHA-256: db41cf474bea96d9bc686524ec77e710ea47efb318d4202157c45c55267e0e78
font_02_sfnt_off00014a76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A76 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1