Malicious PDF — malware analysis report

Static analysis result for SHA-256 638c4372689c9234…

MALICIOUS

PDF

87.8 KB Created: 2021-09-07 07:11:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: b9cb96ce5bf315969e13429fdb4f47c2 SHA-1: 8bafbc8eb9442e631109e1e9382551a7f6d3c97b SHA-256: 638c4372689c92348f7a9bbe1fe46e84913731850d741b331a724d638375b917
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and 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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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://wastran.ru/uplcv?utm_term=bibliography+in+chicago+manual+style PDF link annotation
    • https://bamor.org/userfiles/file/46406553120.pdfIn PDF document text
    • http://modaxch.com/userfiles/files/14576853045.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/viwuremoxawawuz.pdfIn PDF document text
    • http://pensionpoint.cz/userfiles/files/kaxibanobebaka.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/41356827684.pdfIn PDF document text
    • https://protectname.xyz/whoisprivacy/userfiles/files/90574868429.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160758e6009d87---62713225915.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aac1b122201---80184514000.pdfIn PDF document text
    • http://dvarenda.ru/upload/file/42778202066.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609db98371117---10564596353.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46a0acf851---rimaso.pdfIn PDF document text
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1607930986f6a6---297276837.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/7t5tkt2qv9bpi7vububuqhg8p4/67315378742.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/2e6da1fe906713d29f6d5eefb2fb8930/17072369527.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/ribogopezubinigumupe.pdfIn PDF document text
    • https://sanipro.ma/app/webroot/uploaderfiles/fatujarifozexiwe.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/78182988014.pdfIn PDF document text
    • http://crmrealty360degree.in/userfiles/file/23917862220.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/mbrlkiihik7v3lvebf4ff12hq7/15272596112.pdfIn PDF document text
    • http://sns.hu/_user/file/xopozamo.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/4795589253.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_off0000ef7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF7D 18532 bytes
SHA-256: ab424f555d3767314c3895a820a656f828e1e680167586ac039677a2c5ff01bd
font_01_sfnt_off00011f7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F7E 11228 bytes
SHA-256: 87685462e0f66c9d27177c3887d0edecd6b9ebca3373045c8913f72c5e75a2e7
font_02_sfnt_off0001397c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1397C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1