Malicious PDF — malware analysis report

Static analysis result for SHA-256 998a8868b5a37b23…

MALICIOUS

PDF

83.4 KB Created: 2021-06-25 22:21:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dcdee0e5cfcb7bc0310a17f145d393d4 SHA-1: d76e4109014a2ebc4345e84c3c41670f547826c7 SHA-256: 998a8868b5a37b2305f10ab0ed1d1bf962155e9049821cda66217ec835a12225
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF sample was identified as malicious by ML classifiers and ClamAV, indicating a phishing or malware distribution intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, likely serving as a distribution point for further malicious content. The presence of external URIs and the nature of the links suggest an attempt to lure users to malicious sites, potentially for credential harvesting or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • 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.
  • 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://infrive.ru/uplcv?utm_term=rrb+ntpc+question+paper+in+english
    • https://www.amiunaorchestra.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16088714f49281---23113765792.pdf
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a26f809df92---tutevu.pdf
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160800c1a62997---kifekoti.pdf
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c415a23b453---sadolizume.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddecb71536---powimalejufixatanejozegaz.pdf
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6171b9528---14048155027.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16095fe3c1a40d---loludexije.pdf
    • https://ankaratemizlikcim.com/depo/sayfaresim/file/87193388749.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/11u9camo6gkfkvq1ke4ea3ig0h/9418044043.pdf
    • http://aelma.com/sites/default/userfiles/file/1418026315.pdf
    • http://cosmickino.ru/sadm_files/zixezakewumamoraded.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608914ee2c05f---degifimadutufo.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16076761a90396---83535659309.pdf
    • https://tlproduct.com/userfiles/file/kenatalotipum.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/8fbvlm5ivfp1khntq5ki15ohd4/sufapiti.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/6000f7527ed385129af15504448f80f6/56248293588.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/b58230e55e89e01fd6401c1a039dd067/piralujanivigivinefo.pdf
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608b64a619425---88864750420.pdf
    • http://businessplan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/jivifezaliwuvewu.pdf
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e55453ae51---minomajin.pdf
    • http://drwatsonsr.com/clients/2/2b/2b9a0cf27321ceab3a47fbd10bf94d34/File/85206917081.pdf
    • http://www.monts.sk/upload_images/file/16794790068.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_off0000e242.bin
04e08e882163455e6a9a0842493f6b256b3bfbab4e06948e0538efa6c79594e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE242 17108 bytes
font_01_sfnt_off00010f11.bin
61d90253ae492d66080cfad6e4c54178ae919391e7769c2158d933fdb50c177f
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F11 11084 bytes
font_02_sfnt_off00012855.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12855 16792 bytes