Malicious PDF — malware analysis report

Static analysis result for SHA-256 da123a0e6ecf9f6a…

MALICIOUS

PDF

76.5 KB Created: 2021-09-16 07:19:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ec2d499d133fb8052af8c39d8a4885b2 SHA-1: bc74c22e29ae216960529c21adc82a68b087e8af SHA-256: da123a0e6ecf9f6adfa1bb9004b805a3ef98042cb276db750ffd0faae788731c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to multiple compromised CMS uploads and disposable hosting. The document body was unreadable, but the presence of numerous URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/6343b21bfd5ff52daacbc8b882aa155e/83752490628.pdf In PDF document text
    • http://leebyunghun.org/new/upload/board/files/3543594038.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/161424bb86d0fb---85076429992.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613eeb4d7b93a---82226622268.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/vazijimesujumet.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/fuxedu.pdfIn PDF document text
    • https://adamant54.ru/userfiles/files/94209730527.pdfIn PDF document text
    • http://nemalipics.com/5896311066.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/vedoge.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/dakagodoxitixatomisufox.pdfIn PDF document text
    • http://wedding-box100.com/uploads/files/202109031106448240.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/fitopapowaduzebis.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/seravetulu.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/zeruri.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16140be68b1554---10410513097.pdfIn PDF document text
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/4rkhl4d9bb42qecjkh5b46a2s6/kexorotinabibagutopeb.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec729bacf2---pizidovirifajuwik.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/fenomuluruvufulo.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/80963518274.pdfIn PDF document text
    • https://jvlegacyhomerepairsmd.com/nbloom/fckuploads/file/54903814579.pdfIn PDF document text
    • https://red-adlay.com/upload/files/294805083.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/6145824559.pdfIn PDF document text
    • http://spl-designs.com/ckfinder/userfiles/files/xetapuxi.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/28126808183.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=i+am+malala+activities+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_off0000c6ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6AB 17760 bytes
SHA-256: 867c7d26c8bd56b6ea624343430a5f87f5e3bd0e5bb32262092d8e3957ac4164
font_01_sfnt_off0000f48a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CA1 10472 bytes
SHA-256: b696134184c1d7ff92a719160d6f965dfa2ce4b934f93a9cf3b245b7dee1e27e