Malicious PDF — malware analysis report

Static analysis result for SHA-256 717b75186e4ee417…

MALICIOUS

PDF

77.5 KB Created: 2021-09-02 16:35:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cbaafae62261e89a430c95e640b09e34 SHA-1: 35752faede366bace5eed3ca2f45616ba8ab52d9 SHA-256: 717b75186e4ee4171de65d94d77366ae4901c3c99b20d2d13fb2cb075fb3887e
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier strongly suggests malicious intent, likely to lure users to malicious sites or for SEO spam. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://nomylo.ru/uplcv?utm_term=forever+lyrics+and+chords+pdf PDF link annotation
    • http://18554080.com/userfiles/file/gowewagukaviro.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/23788329875.pdfIn PDF document text
    • http://podlahypilat.cz/admin/file/kopifiluxexupezojifa.pdfIn PDF document text
    • http://partner-support.net/user_data/userfiles/files/5097722115.pdfIn PDF document text
    • http://www.jobsincrete.gr/images/_user_na/file/gibulepokolonexuvajuwog.pdfIn PDF document text
    • http://imbirimbir.ru/files/55353550233.pdfIn PDF document text
    • http://hanart21.com/files/userfiles/file/fezidaludajezepoxalajofe.pdfIn PDF document text
    • http://historia-bfured.hu/userfiles/file/10612673256.pdfIn PDF document text
    • http://szao-spb.ru/images/news/file/3007488257.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b64994ba37b---tixutusok.pdfIn PDF document text
    • http://capitaloffice.pl/fotki/file/mukoma.pdfIn PDF document text
    • http://pensjonatagat.pl/userfiles/file/gedujelerakolixowosadado.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfcb058d95---37998229147.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/1df6ehrbtvq8cq0kgri1379es3/gifexu.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f831f5e63e---3988571040.pdfIn PDF document text
    • http://vektorma.ru/uploads/assets/file/sefosadijixeto.pdfIn PDF document text
    • https://geniodelweb.com/file/sikixabumajogekupakum.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/ae8af26c91029fdda1059c9810a0464e/34140503132.pdfIn PDF document text
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/80108ee4a5d2d658c689bd9b581c5b85/15809310140.pdfIn PDF document text
    • http://www.heksan.com.pl/file/60011620699.pdfIn PDF document text
    • http://sancheonglittletheaters.com/upload/userfiles/2021/08/files/210803081338.pdfIn PDF document text
    • 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_off0000c8c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C7 18452 bytes
SHA-256: a0d10eaede87a55b9551dd70c9fd34c1966791cee16bfedc222f93d7cddc6053
font_01_sfnt_off0000f83d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83D 10776 bytes
SHA-256: e2d61a3e9e5411504b7e1f2c2fb3f285fba89b20c173ceb4937bdd4813c9c213
font_02_sfnt_off000110f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110F0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1