Malicious PDF — malware analysis report

Static analysis result for SHA-256 e61ee543c7130a9f…

MALICIOUS

PDF

78.6 KB Created: 2021-09-22 11:44:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 981d7b89ed254e85e48ca2e0d17e3b18 SHA-1: e931552cc926ab14f7dfa691054a5ad383bc2ef4 SHA-256: e61ee543c7130a9f8fd7b75e5309c775e7446dc4def18f262eaefbbfe59e7f6b
156 Risk Score

Malware Insights

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

The sample was flagged by ML classifiers and ClamAV as malicious. It contains numerous external URIs and link farm patterns, indicating an attempt to redirect users to potentially malicious content. The presence of compromised WordPress upload links suggests a technique to host malicious files or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://inwebjor.ru/uplcv?utm_term=my+battery+saver+apk PDF link annotation
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138c4db7990a---79339246808.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/oh3e85dc9kb1uioslsq42c7cj7/22011613051.pdfIn PDF document text
    • http://mybed.tw/uploads/files/202109161946482718.pdfIn PDF document text
    • https://cubic.is/userfiles/file/5206672642.pdfIn PDF document text
    • http://antropolog.ru/userfiles/file/wozawavat.pdfIn PDF document text
    • http://getwealthythisyear.com/ckfinder/userfiles/files/68313134333.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/dipumuzuxagigaruzuriz.pdfIn PDF document text
    • http://korea-labels.com/ckfinder/userfiles/files/97914976032.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/vapotifujagamedaxal.pdfIn PDF document text
    • http://pmke.cz/pictures/files/wezufebapinasadizavidufu.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/43689381570.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/vubura.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16317553014771.pdfIn PDF document text
    • http://chhattisgarhsanskritboard.in/sharpinstitute/images/files/zazuzidalumas.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161414a2845c2b---31565460189.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/volazorewitidasojeka.pdfIn PDF document text
    • https://tezerwatch.com/file/upload/files/09-22-07-21-07-66.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613d985aab6e2---borubulusibuxoguvajiteson.pdfIn PDF document text
    • http://ornito-silesia.eu/userfiles/file/70641169285.pdfIn PDF document text
    • http://agilesolutions.in/uploads/livopulitum.pdfIn PDF document text
    • https://dolmalatrek.com/userfiles/file/murekopa.pdfIn PDF document text
    • http://shosholoza.de/file/83700580787.pdfIn PDF document text
    • http://pkpneu.cz/userfiles/file/10483376432.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_off0000d162.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD162 17004 bytes
SHA-256: 1568ba089c35e0060b2fe6fc20cd3cd95b5dd50cc426b2d7538b237442196011
font_01_sfnt_off0000fd50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11567 10288 bytes
SHA-256: c6e934026e0a16659ae5da0960a2bf176c7a040ee0b9a33e06cacc1c4316d262