Malicious PDF — malware analysis report

Static analysis result for SHA-256 b458c40934f2dd2f…

MALICIOUS

PDF

82.5 KB Created: 2021-09-04 05:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6f27761ba72eb8afe75bffd8dddb1263 SHA-1: d77dae25d408a665f3c78494261e4b1407f77343 SHA-256: b458c40934f2dd2fbba68a5fdd42493c461d3ec38ca21f58aff697b2c10ddf1a
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to redirect users to phishing sites or to host further malicious content. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF designed for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://ombs.ru/uploads/files/nujegetamimafose.pdf In PDF document text
    • http://jr-bang.com/uploadfiles/20210726005018.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/tusilawogutijesoka.pdfIn PDF document text
    • http://guitarenko.fr/img/files/28036552744.pdfIn PDF document text
    • http://m4klynchburg.org/clients/3/34/34420611de4c9c7593cf5e5fe12de6df/File/xedazur.pdfIn PDF document text
    • http://niestachow.pl/data/aktualnosci_imgs/file/lanuzimalajasazejarafijaw.pdfIn PDF document text
    • http://antichigelsi.it/userfiles/files/42975766814.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/17217543549.pdfIn PDF document text
    • http://delawaretravelmedicine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d097df11df---tajoj.pdfIn PDF document text
    • http://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc103236eb---vuxipulumujuxow.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/kazuvozarawalera.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/kolurisaniwowejunobid.pdfIn PDF document text
    • https://lixtech.com.tw/ckfinder/ckfiles/files/84559584921.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/torepajanobaremiriwud.pdfIn PDF document text
    • https://rmduncanrealty.com/userfiles/files/69312776879.pdfIn PDF document text
    • https://duel.pl/userfiles/file/rulanunewu.pdfIn PDF document text
    • https://gea99.com/ckfinder/userfiles/files/6745552159.pdfIn PDF document text
    • http://nkcophs50threunion.com/clients/0/01/014062e559e26c1cf0711bcec4e573ae/File/batiwulabawidafopiwefig.pdfIn PDF document text
    • https://kompaspt1.com/contents//files/69765080259.pdfIn PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c6999a3aba8---68309684875.pdfIn PDF document text
    • http://copy2d.com/ftp/image/file/xopivexuner.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=mesotelioma+pdf+elsevierPDF 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_off0000d955.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD955 20008 bytes
SHA-256: 9f984d0427a9f94a07eb41fbac915e2e4e93790c550a87afcdb519d110f2571b
font_01_sfnt_off00010c95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C95 10616 bytes
SHA-256: df06dcdc3d7942603ef9cbb54ba5530f135ed2b7b7237395df73ab302ec3563d
font_02_sfnt_off000124e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124E7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1