Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9165d7d4df9f976…

MALICIOUS

PDF

93.0 KB Created: 2021-07-04 06:01:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 142a3ed84cca7c53466c9ffc63ca5c11 SHA-1: 9f855ee64f5406628e8fea42ade027b75fb542e6 SHA-256: f9165d7d4df9f976bc289d3bc0beaabc3b815d4cea54c3f3cfc5774e1e3247dc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely facilitates the redirection to these malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chcial.ru/uplcv?utm_term=elastic+potential+energy+equation+physics
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b80023999c---kufabiripi.pdf
    • http://1137.jp/app/webroot/js/ckfinder/userfiles/files/90833354000.pdf
    • https://www.eziblank.com/wp-content/plugins/super-forms/uploads/php/files/2f270b12e4aeab1e78f901de65e40a96/linegaduniki.pdf
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/5a2078c6dd7b83f610bc193d08877ae7/gekikitoriwuka.pdf
    • https://tonitomov.com/picture/file/walijazokefi.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab04864d439---miludet.pdf
    • https://actorconseil.com/files/file/tefepigex.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608c622c62eec---94806214843.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609a95bc2d44c---nopejoduruwufubiwi.pdf
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/49702249837.pdf
    • http://anhuizpyy.com/upload_fck/file/2021-6-20/20210620033553401220.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1607702ed2a216---kojadidijupederarak.pdf
    • http://altaprecision.com/userfiles/file/nagaga.pdf
    • http://expertsystemgroup.com/file_media/file_image/file/sawibi.pdf
    • https://alihuata.com/userfiles/file/52279827880.pdf
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/62daab05d7dd7619f5dca217508e2957/dukutu.pdf
    • http://richmediahouse.com/admin/uploads/file/xadidotinozomaramud.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c888d10ec74---teleboxafolawu.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cede64466c7---76745302272.pdf
    • http://hanasushimenifee.com/uploads/files/12618252567.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/e26e73372fe82491a50449b8c786c501/dasukajusudiwovenejuwovew.pdf
    • http://sequoia60.com/clients/875776/File/faxexanuwasolekumobomeva.pdf
    • http://zabradli-znerezu.cz/userfiles/file/remagedipewurubolaxozo.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_off000101aa.bin
7e04744b592eaf5122a294a579fc9bad44db9d695639d698ebf5f65a2f76345a
pdf-font-stream PDF embedded font (sfnt) at offset 0x101AA 10996 bytes
font_01_sfnt_off00011ae1.bin
2ebc1b0b53a817bc98f484b3cf3bd52f5fdda8d5433f1c7a96c67640dfa106c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE1 19008 bytes
font_02_sfnt_off00014ce2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14CE2 16792 bytes