Malicious PDF — malware analysis report

Static analysis result for SHA-256 726221bd564f9f34…

MALICIOUS

PDF

77.2 KB Created: 2021-06-09 17:49:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 35e486c2378ef7f94ecef8564fcc0fc2 SHA-1: 2fcf5c02187e4b0474656e2efb81b9f65df1ff29 SHA-256: 726221bd564f9f3415dbdd0f98b0c25d2a78605794f31f82947ce59a92c2c6ff
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised CMS upload directories, suggesting a link farm used for phishing or distributing further malicious content. The PDF structure and embedded URLs align with common techniques for luring users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://huntic.ru/uplcv?utm_term=british+english+grammar+book+pdf PDF link annotation
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/de68d67c09d948fc27bcca5ea65bf865/sesowivuzipolufo.pdfIn PDF document text
    • http://perfekttorun.pl/pliki/25560591618.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/0c9c99b9e901b5d3424911fbc12edcf2/75482355860.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16083303f1f014---daratojebebes.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094cb5c278ba---12151175192.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/92578969021.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160838e8094b9e---71496244834.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160988a24b4c17---vives.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16088a858558df---25775071039.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/e5segm1eg1lrieccu74aj3qp04/kodonipuxa.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1ffd69da1---zagapoguwi.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/78417468698.pdfIn PDF document text
    • http://ipceurope.eu/assets/file/fugonifuva.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/29c25bdb3b85029453d11e15c9a8a98b/2622251920.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/d34c2c3ad9b0f61935ccc65681385855/66927449218.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE31 5708 bytes
SHA-256: e74dd77ecc45b7c6ff66e2fc1353236f392ee340128528fc51f2a3d523f1bce6
font_01_sfnt_off00010171.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10171 11536 bytes
SHA-256: e363c7885b35645f5f8881ff1cfb580865d674dab1ce165ade6bd19060627090