Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d73a898c624efd3…

MALICIOUS

PDF

76.6 KB Created: 2021-09-13 14:21:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b0e6b3b6e810c177c27a3ffb40478a9f SHA-1: 2c211c36a35ed15d98caea686c9e41dfe45751c1 SHA-256: 8d73a898c624efd3499c2e2f8c07b8137944adf81968190b9ee228ed67c89d33
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The file's structure and URL patterns are consistent with malware designed to redirect users to malicious sites, potentially for credential harvesting or further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 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://ck-kutnahora.cz/gais/image/file/jozevazatemiguxedu.pdf In PDF document text
    • https://lochoanggia.com/upload/files/fuxitagewipilagotigusoxux.pdfIn PDF document text
    • http://compow.net/ckfinder/userfiles/files/jafapoxe.pdfIn PDF document text
    • http://bloemenwinkelindex.nl/images/uploads/bikusu.pdfIn PDF document text
    • http://at2apigroup3.com/contents/files/62735965070.pdfIn PDF document text
    • https://orangcar.com/app/webroot/upload/files/jotadejarodivalegezopaz.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/gosadivaj.pdfIn PDF document text
    • https://abcoegypt.com/userfiles/files/44379788652.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/egjeoe9kbeokoda5tc2p9nvrg9/72431517446.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/161338b0cb0cbd---61087868185.pdfIn PDF document text
    • http://odpadykj.cz/UserFiles/File/vineg.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/43119473736.pdfIn PDF document text
    • http://tivatijapan.com/uploads/userfiles/file/39095016430.pdfIn PDF document text
    • https://tannhatviet.vn/upload/files/83035579519.pdfIn PDF document text
    • https://connatlas.com/home/conn/public_html/ckfinder/userfiles/files/28686037724.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/25338546582.pdfIn PDF document text
    • http://ttfi.org/app/webroot/userfiles/file/52746207376.pdfIn PDF document text
    • https://beaumont-residence.com/wp-content/plugins/super-forms/uploads/php/files/9t8avsbp0gqh6sn5iir733kudq/tatesopowovubapowosan.pdfIn PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/98595413198.pdfIn PDF document text
    • http://schokofontaene.de/idata/disofisaxuwosujevumufi.pdfIn PDF document text
    • https://best-label.com/upload/files/58217009475.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/mukegaropurituf.pdfIn PDF document text
    • http://goldenagegroup.vip/userfiles/file/kosawejatixadedajorizud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=glencoe+algebra+2+practice+workbook+answer+key+pdfPDF 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_off0000c534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC534 17460 bytes
SHA-256: 8e14494c4b90dcb1fa320115ec5e8f3f0f5f5ee06fee3861a0ff9a74eafd6f09
font_01_sfnt_off0000f213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF213 11388 bytes
SHA-256: fa646edb5dc22c0a08727c73a540601062ca00a6991d68a5bff51fa782723e38
font_02_sfnt_off00010cc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1