Malicious PDF — malware analysis report

Static analysis result for SHA-256 d82779598465e1bf…

MALICIOUS

PDF

74.5 KB Created: 2021-06-11 02:35:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 4918e9506ddd4793763ff7b3123d973a SHA-1: a3da6f3e36e9ba635e19a023abbf342ebb42f27c SHA-256: d82779598465e1bfa2281b144338f46ac1abbebb766d9a14f4430cba3dbc2a37
104 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crewmak.ru/uplcv?utm_term=6+std+tamil+book+pdf+download PDF link annotation
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/f1ca2121050fd1a31f9d9a9485c1e348/30196993812.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/85057555881.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160772ded7545a---sizamewixadalezuxidamo.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/16094d72286a75---24434083796.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/bakorenutek.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c2434e0f337---34997684895.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a32451418b7---sepibuxem.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb69fb0b11---bogexolixepekegarile.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a5991e8e662---10971769018.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/ad0e7b042d581a2a0d3187c7d6572caf/72797150794.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16071812d0337f---sebitibaxawaruwapa.pdfIn PDF document text
    • http://trustarshida.co/cache/fck_files/file/32933153679.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/44644836644.pdfIn PDF document text
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/44819278692.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E2 5448 bytes
SHA-256: 6bd2ba65c031075f02266dac26750f304071d3f818537905deba27b2b71e5472
font_01_sfnt_off0000e662.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE662 6308 bytes
SHA-256: 6f1685934922f68e0eeb97fbdb292f5406ac8757fd375788892a6af9a1be1d78
font_02_sfnt_off0000f9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 10396 bytes
SHA-256: 6bf8974ab4b6dfd1fbc0d69f5eedb719056809541414724a1089d833e69e34e0