Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4a5611e16a3e53c…

MALICIOUS

PDF

79.3 KB Created: 2021-10-06 23:51:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a8c42417872c2bce26c9f56e57c704af SHA-1: cb0f57a5ac0224b791323969c99266b40d9127b1 SHA-256: c4a5611e16a3e53c52a2cc14f328ecfd200b75c66659b2fb91f3f804272b7df1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which are hosted on disposable domains, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://archism.ru/uplcv?utm_term=the+progressive+movement+1890+to+1920+worksheet+answers PDF link annotation
    • https://ltssinternational.com/res/wysiwyg/file/momik.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-30/20210930160908281818.pdfIn PDF document text
    • http://himalayakebab.irafbrothers.com/shipinc/userfiles/files/2441817380.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1615d434546ab4---xemoxonizasi.pdfIn PDF document text
    • http://mrukseo.pl/userfiles/file/22028261108.pdfIn PDF document text
    • https://digitaluzaktanegitim.com/calisma2/files/uploads/62714372252.pdfIn PDF document text
    • https://cuatudongnhatrang.com/uploads/files/62529746825.pdfIn PDF document text
    • http://asv-solnice.cz/_files/file/1530809783.pdfIn PDF document text
    • https://pmeds.us/userfiles/file/narilani.pdfIn PDF document text
    • http://ingore.cn/upload/files/tesegu.pdfIn PDF document text
    • http://ort168.com/upload/ckeditor/files/puluwadijomorurexiv.pdfIn PDF document text
    • http://happyland-nsk.net/ckfinder/userfiles/files/bizomaro.pdfIn PDF document text
    • https://vsevolozhsk.mebel18.com/uploads/files/68484563726.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/6a8b335cac9d610830315b457de5667c/gekaramav.pdfIn PDF document text
    • http://man-shoes.moscowfashion.net/content/xuploadimages/file/ferolipababusavap.pdfIn PDF document text
    • http://lakesnwoodskerala.com/uploads/file/87859625584.pdfIn PDF document text
    • http://chromavials.com/d/files/woxalamufofap.pdfIn PDF document text
    • https://brakos.it/file/36766471979.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-16/images/files/80428714506.pdfIn PDF document text
    • http://laureysnv.be/uploads/files/nefoma.pdfIn PDF document text
    • http://strojsteel.cz/webpagebuilder/ckfinder/userfiles/files/65863008234.pdfIn PDF document text
    • http://www.aaar.cat/assets/js/ckfinder/userfiles/files/wapazubimojiwatunap.pdfIn PDF document text
    • http://www.portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/kinabe.pdfIn PDF document text
    • https://luxurybaths.marblobaths.ph/app/webroot/img/files/41399733385.pdfIn PDF document text
    • https://www.canoe.ro/Extras/ckfinder/userfiles/files/77101252405.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_off0000d035.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD035 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e847.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE847 16944 bytes
SHA-256: aef7e64ad3622aacf21ff288b89d4f8b32cc1cb1e52039cc814ee26d1d53b9cf
font_02_sfnt_off000113bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113BD 11528 bytes
SHA-256: ca27568c270e3313c944323880b51e2f79089c9d7599c49eca8eceb71243c908