Malicious PDF — malware analysis report

Static analysis result for SHA-256 8013a70ca3125578…

MALICIOUS

PDF

83.1 KB Created: 2021-10-07 07:54:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d9772bb2d80127633e5114da901def0b SHA-1: af737f71a1649bef4375886481e2ec3243198349 SHA-256: 8013a70ca31255782785d21da515f402884fe4fed6fa1e88d99f1769588f8ae1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress upload directories, suggesting a link farm or phishing lure. The PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://garglob.ru/uplcv?utm_term=high+priestess+yes+no PDF link annotation
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1615acfeb1825a---95587873366.pdfIn PDF document text
    • https://phongkhamtamthan.net/uploadeditor/files/13261404255.pdfIn PDF document text
    • http://bio-scan.com/userfiles/file/45632817808.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/nafiwika.pdfIn PDF document text
    • http://airserbia2009.vs.rs/multimedia/file/60609681556.pdfIn PDF document text
    • http://www.wcd.com.tw/ezadmin/ckfinder/userfiles/files/zodufoposubavu.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b26901b6c7---tagume.pdfIn PDF document text
    • http://hpworld.hu/data/pic/Image/file/dujoravimizi.pdfIn PDF document text
    • http://pradakshinam.com/fck_uploads/file/87612421931.pdfIn PDF document text
    • https://km2804.com/ckupload/files/dugixivijubub.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/batazitutugegox.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/43556606784.pdfIn PDF document text
    • http://haithuanphat.com/uploads/files/46231088362.pdfIn PDF document text
    • https://mbbs.hr/files/19152121670.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/364d9dr8tliea4uh8eii34rrs0/533177187.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/161511622b6562---bapozezazerozakil.pdfIn PDF document text
    • http://panova-art.com/files/file/2752711474.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/47768796690.pdfIn PDF document text
    • https://veriniams.lt/userfiles/file/1588016680.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/88024696278.pdfIn PDF document text
    • http://tomaszbizon.pl/web/uploads/files/8181731449.pdfIn PDF document text
    • https://www.kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/lakize.pdfIn PDF document text
    • https://warsztatgdynia.pl/app/webroot/media/files/93372536015.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_off0000dae4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE4 19940 bytes
SHA-256: 87921a936615870eaf7d71b5d06ccd5d2717adf4aed7964bd91a37914133beb2
font_01_sfnt_off00010ef2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EF2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012709.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12709 10428 bytes
SHA-256: af3dd783bc6fc75f620e187ffb97242cf373ebee87d10d7b4315d2b12919d62b