Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9773736a74de095…

MALICIOUS

PDF

89.2 KB Created: 2021-07-29 09:42:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 77e078a4986663c36d41917e9ae32cb4 SHA-1: 21f39ff2fa9341b93f858472b8f4fdf1dc358684 SHA-256: c9773736a74de0954e7ae008df8f866214a5df75bf9942175c47fa35aaa450b1
96 Risk Score

Malware Insights

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

The ML classifier strongly indicated maliciousness, supported by heuristics identifying the PDF as a link farm pointing to compromised CMS upload storage. The document's structure and numerous external links suggest an attempt to redirect users to potentially harmful sites, possibly for phishing or malware distribution. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://ukmalayalamnews.com/userfiles/file/lotapipunuzaxoji.pdf In PDF document text
    • http://myblindz.com/fck_user_files/file/waxujilipavexevejimamara.pdfIn PDF document text
    • http://doubler-son-capital.com/photos/files/forikasunadixizexibuxavu.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/38373579491.pdfIn PDF document text
    • http://ippinnudon.com/uploads/files/subikilokavoxukavapafe.pdfIn PDF document text
    • http://osrclass1967.com/clients/8/84/84e84eb3bb32f45446e669e24fea3ebc/File/gorikasadakotofu.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160809f04e7c11---manimur.pdfIn PDF document text
    • http://candientu24h.vn/webroot/img/files/99116302558.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160874c7493d60---58959581679.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/08a4e7987c3e7c26e689a93e59e469c4/vetafi.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160f88704df630---52175938857.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20210618_AC9C870BE94D67BD.pdfIn PDF document text
    • http://colleges-in-tamilnadu.com/FCKeditor/userfiles/file/tarusasunulapanitexev.pdfIn PDF document text
    • http://technocom.pl/editor/file/magutuxe.pdfIn PDF document text
    • http://vinhomeshaiphong.net/app/webroot/img/files/39895157504.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/dcf2ac44b664672bba7308a599ad7386/50512062344.pdfIn PDF document text
    • http://marcus-1.com/FileData/ckfinder/files/20210607_BE81AC67D8EF5DE0.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles//files/movekusugatuti.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f7726ccc9d18bd0e7d98bdda16696195/38579922992.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e14b2f841---radifalozo.pdfIn PDF document text
    • http://synerfreight.com/syner_upload/images/files/91636098125.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=does+moringa+burn+belly+fatPDF 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_off0000f90b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF90B 10912 bytes
SHA-256: 9f562c469f2928672b41fccede95b99533cc5afcbf2eb8ce6fd9bcb16fd2c413
font_01_sfnt_off00011256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11256 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A68 17344 bytes
SHA-256: 28f115aa302b5bb1fae0a78d6ca6b1c0119da471a88be486928fa1d9c6596866