Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1d4bb4684fe65dd…

MALICIOUS

PDF

85.6 KB Created: 2021-06-26 22:07:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d52b28b0b1b59a7bf551f8f80f7d555a SHA-1: 837976268724de703b5b67091d16f13dff8a050e SHA-256: c1d4bb4684fe65dd32d3daf5c753d1e6bc1cf954cc041d60f2413be45f239118
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised CMS uploads and disposable hosting, indicating an attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious. While no scripts were directly extracted, the structure and embedded URLs suggest a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://edwardlankin.com/clients/86087/File/49494576432.pdf In PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0f068bed5---31983916469.pdfIn PDF document text
    • https://appchecar.com/ckfinder/userfiles/files/21595241376.pdfIn PDF document text
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/c0d756cdabc3032656cfdc0ef240a61b/82959118351.pdfIn PDF document text
    • http://cgl.lu/userfiles/files/jisubokegexasixuziwak.pdfIn PDF document text
    • http://www.mondzorgvesa-voorschoten.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607461f8a21b3---19872642824.pdfIn PDF document text
    • http://josephlillianmorrisfamily.com/clients/59960/File/73553214709.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/69698962066.pdfIn PDF document text
    • https://blindnow.com/userfiles/file/36922531668.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160900fac8256f---26457564512.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/96521417024.pdfIn PDF document text
    • https://www.cr-sdc.org/wp-content/plugins/super-forms/uploads/php/files/e85288ca5c0fe516c1a7105ea5dd3170/sokotufakibanupodo.pdfIn PDF document text
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da0f18feb1---loverakate.pdfIn PDF document text
    • http://cgl.lu/userfiles/files/wusomazesurebaluga.pdfIn PDF document text
    • http://cnhhgj.com/upfiles/userfiles/file/nuvutolosutifo.pdfIn PDF document text
    • https://detectiveoffice.net/userfiles/file/77215311932.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608166e1ba5be---99284616321.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079fb57ba241---37419854491.pdfIn PDF document text
    • https://aashianarealty.com/file/najebunugevawawabusexuxa.pdfIn PDF document text
    • http://bafiti.com/sklep/userfiles/file/59948555215.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160725642539a8---6961284831.pdfIn PDF document text
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/2cae81f8aed9a2f166e6e1558d188d30/dobagujivipunovad.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/5eb6a1d792c8544641752e265b1ce292/soxufubifomug.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=active+passive+basic+rulesPDF 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_off0000ecf3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECF3 16672 bytes
SHA-256: 4b46d33982572d3ad2decb8a5bef531cab6cc71edef74d3e9551b634dcb146da
font_01_sfnt_off00011806.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11806 10428 bytes
SHA-256: d6307180a256c13a69e754e6a7bd48a56c78cb97afbec6ddf54c7e8da20ffbbf
font_02_sfnt_off00012fa6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1