Malicious PDF — malware analysis report

Static analysis result for SHA-256 9923cfd24bd88135…

MALICIOUS

PDF

76.2 KB Created: 2021-09-05 20:31:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e317f44112430d01d0abe3e449c93edc SHA-1: b83b9dc5b2450a218ef6f4a61c3a6f34a116e0fa SHA-256: 9923cfd24bd88135f8adf9c07e6dff60d46e8c62384009a57896b669971033cf
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://queure.ru/uplcv?utm_term=antepartum+haemorrhage+management+pdf
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/kq8tcag6r6m9ovgsuds5rl4h6f/2574788650.pdf
    • http://kondicionery-krasnogorsk.ru/upload_picture/file/gusagosugegudokofukal.pdf
    • http://knuhpharm.kr/userfiles/file/20210708050508.pdf
    • http://whscardinals1963.com/clients/9/9e/9e5fab02d16e7113a74bdd4e7828f974/File/wufonemotiveg.pdf
    • http://toddfamilyreunion.com/clients/4/48/482e924d5a052aa4a0c13eb8a30e0bc8/File/13457019412.pdf
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5414b1ee72---vutumu.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1af9e94b62---rijaxitusowub.pdf
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//bogifelawazepuxofodel.pdf
    • https://jensbrode.de/files/file/siginalaxovuwozezekefafiw.pdf
    • http://pogservice.ru/userfiles/file/78338836661.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160f9d23bdf73c---gawemubafezabunetub.pdf
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/1e6674cb8eb5a0200944f39021e71b64/88504246974.pdf
    • http://emailreceptionist.net/userfiles/file/mutiduvaxolobozufo.pdf
    • http://kaupa.cz/userfiles/file/49394097407.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/gafmot8bmv390cfpj71rjc5khc/16789851601.pdf
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/6e0c501fe280fd6c9935b3b657ab8e90/63133349176.pdf
    • http://crosswaysrecruitment.com/userfiles/file/57720805908.pdf
    • http://radio-salsa.com/php/rs/filesupload/file/jutawiges.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f97b1491400---42307527430.pdf
    • http://wsp.pl/userfiles/file/19124808364.pdf
    • http://fritz-fahrlaender.ch/download/ranikibo.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607eae5571967---viretopinibetu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c5be.bin
8edb0288a0716668c215f8af32df1e421539ba108ca76fc5701de268f5dc2f91
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5BE 17640 bytes
font_01_sfnt_off0000f33f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF33F 16792 bytes
font_02_sfnt_off00010b56.bin
c470794ee8e07563da7fb858a91bd09fbbba5a1a416cde4e67db9d68200c2707
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B56 10720 bytes