Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b69f6d593c90126…

MALICIOUS

PDF

89.6 KB Created: 2021-07-28 14:33:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 5fa0baa5b919f79944ce37bcb8432ff9 SHA-1: c13ad46730f1d520a1d575c0314a471cbfff316c SHA-256: 8b69f6d593c90126a41034a1386b0a5a85154522b61969a535d84c45d37701e5
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, which in turn host other PDF files. This suggests a tactic to distribute malicious content or engage in SEO poisoning. The ML classifier strongly indicated maliciousness, and the structure aligns with techniques used to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607dc7501d338---lomasoziwedaxomatu.pdf In PDF document text
    • http://optikametuje.cz/userfiles/file/daragud.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce8ab620e7b---88822898585.pdfIn PDF document text
    • https://masini-de-ambalat.ro/images/userfiles/79736743263.pdfIn PDF document text
    • http://immobiliareborghi.com/userfiles/files/tagopupa.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/1a25169bcd824763c59b965588a72ee1/78001604617.pdfIn PDF document text
    • https://soechi.id/userfiles/file/8435954503.pdfIn PDF document text
    • https://smilaxlabs.com/userfiles/files/tepibinidirinazenovatewib.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/37704039311.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/5c42281d39fe9568dcc839e01492787d/10246823154.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/toxidupug.pdfIn PDF document text
    • https://producedepot.us/userfiles/files/64539042668.pdfIn PDF document text
    • http://abwingsbuffalo.com/uploads/files/29917186730.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bec85b14bb7---xuvoveverazonapewidivawo.pdfIn PDF document text
    • http://beijingbeat.com/contents//files/22946572613.pdfIn PDF document text
    • http://poltinik.ru/userfiles/file/76717022909.pdfIn PDF document text
    • https://csn-alliance.com/data/files/31661935948.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609fef3f19fc7---88379509225.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609559ef693ac---fubesakowixujaxajive.pdfIn PDF document text
    • http://amy-tsai.com/images_express/userfiles/files/55866350571.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=blackweb+bluetrace+mouse+manualPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA76 10768 bytes
SHA-256: e4a1e183c876325eb00272fb3fd610785780242fd0cfa9d0e69d65a35ea175f7
font_01_sfnt_off0000f36a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B7B 17160 bytes
SHA-256: f4a3cfd8c321d5069927428fb1cf6922bc58f76fd8b689f65626fdb7591fb2ee
font_03_sfnt_off000124f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124F1 20452 bytes
SHA-256: b8e0f21c07eca69c0f34bc06d60d2c8d877789e9ba2cefede72e24adf3b36afd