Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b3a4f464fc95de6…

MALICIOUS

PDF

80.4 KB Created: 2021-08-13 23:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: cb1cc6511286195fdeaabdd3ade72350 SHA-1: 51a63347372ac90c646e7e6b992298d6d4f94dad SHA-256: 3b3a4f464fc95de68a54a3efb709ab16d7214e979ef79161c6a769d0d6f4a033
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal a significant number of embedded URLs pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to distribute malware or conduct phishing. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9092

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 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
  • 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://irlanc.ru/uplcv?utm_term=el+principito+2015+pelicula+completa+en+espa%C3%B1ol+latino+online+gratis PDF link annotation
    • http://chobacgiang.net/webroot/img/files/badorikoninimesuvikifidu.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/161032bc8b0915---tatekasuwoluke.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/cf273798bcb38bdbac0adc5bfbc0ae5b/63451203493.pdfIn PDF document text
    • http://furkansigorta.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160fb0b3dd2b42---puvimefeduvawelerew.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/54905460996.pdfIn PDF document text
    • http://homespakistan.net/magzine/uploadfiles/file/xadofe.pdfIn PDF document text
    • http://abwrichmond.com/uploads/files/12021052681.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/cbecc4a825ded228ecbfa9deaf4885cd/8107987299.pdfIn PDF document text
    • https://unitytradecapital.com/ckfinder/userfiles/files/wibivuvitegifusa.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/69478737429.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/3ffd7249ddaeeae2cccad0a6996f0c38/16303635189.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160897ae3ee38d---dareje.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fae311a742---53619463072.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/xabegaro.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/decafbbd4b2818179b38b884e422dccf/91960312573.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/rnn0qkrenalr29n9hk9ct2kld6/fuloxopawajimekarerukejej.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/20862676701.pdfIn PDF document text
    • https://kham.vn/userfiles/file/64862951693.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__60D1A14E9B33E.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/fb00135299466fc3094ef3f6a0f1ee1f/85049577418.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/23299438382.pdfIn PDF document text
    • http://afgventuregroup.com/cfiles/file/74529383189.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000108a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A0 11436 bytes
SHA-256: 9d44354ba7656d33cae55ab5683cf50d1643f6cc05a8165027403f889e7fddb0
font_01_sfnt_off0001237c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1237C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1