Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5402e61c20b7d78…

MALICIOUS

PDF

93.4 KB Created: 2021-06-29 05:58:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8f7708ffef651163620fbc6ff3f3fcdd SHA-1: 5fdaebeca69101754cfe3bd3ce15782367610e68 SHA-256: c5402e61c20b7d78be82d80d52ea41c0122f96d63cca907995bbdebd70f8d2af
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. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting a phishing or exploit delivery mechanism. The embedded URLs lead to various PDF files hosted on potentially compromised or untrusted domains, which likely serve as the next stage of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://e-tta.com/app/webroot/userfiles/files/zevasi.pdf
    • https://pasarantogel2.com/contents//files/webubuzabolefaleparuvokov.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/69d8ead3f283b165261451c0cdf3d521/39477336586.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/khj528dlvp043q61p4gqlhdd82/ziludog.pdf
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c14f9b476a8---kebizis.pdf
    • https://fenixfalt.com/userfiles/file/xelasavitinejagexo.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071001e0b537---45260488030.pdf
    • http://purifoy2020.com/clients/1/11/118d8b7ee1ea4bab8fb19da95c56260f/File/60545862868.pdf
    • http://brlairport.com/images/file/tupim.pdf
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/f0f0f7b5aaa26a51a7420e199ada3397/57661362483.pdf
    • http://xn--k1akb4c.xn--p1ai/userfiles/file/revolutababi.pdf
    • http://sosnovgeo.ru/userfiles/file/13651411787.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4bf417fd30---13215139762.pdf
    • https://sanidom.pl/img/file/13044670112.pdf
    • http://alnadaoil.com/userfiles/file/13897698127.pdf
    • http://balone.net/_upload/file///jexem.pdf
    • http://cukiernia-waltar.pl/qcms/userfiles/file/vopofesu.pdf
    • http://actlogistic.vn/upload/editor/files/jijatajimaped.pdf
    • https://jetzterstrecht.hamburg/wp-content/plugins/super-forms/uploads/php/files/ob0ir5gq8bus7u5hp0frcjqvto/49458262311.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/4472377aba684cca0bc0196c62909460/wifola.pdf
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/1avvf114f66vd6mofo6o47f1ts/77182784272.pdf
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fd347231cc---vevinoniluzozudibuxefufe.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087c36b1b883---fopewoxazunojujurovugipu.pdf
    • http://hongdanhaudio.com/luutru/files/2767388675.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=demand+pull+and+cost+push+inflation
    • 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_off00010838.bin
704d60f258742eebf71663aa33ab0102fc1c6fe985fd21cf19add5f260e6528a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10838 10888 bytes
font_01_sfnt_off00012129.bin
46a845ceebdf46b8d7460f5f860df686d776726f85fa2853be15e7bc0eefab58
pdf-font-stream PDF embedded font (sfnt) at offset 0x12129 17928 bytes
font_02_sfnt_off00015027.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15027 16792 bytes