Malicious PDF — malware analysis report

Static analysis result for SHA-256 c83c8c9f750c2f40…

MALICIOUS

PDF

80.8 KB Created: 2021-09-13 18:51:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5f6afdb501fb6c6b2f02d90717df6101 SHA-1: b476a454554ad66e6af9cda209860e19150c5952 SHA-256: c83c8c9f750c2f40fbff8d2055fca4fd9a24476eba91221ea5c480ef1ff66a54
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to potentially malicious or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM suggests a link farm tactic, aiming to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://www.corpeverest.com/ckfinder/userfiles/files/sapote.pdf In PDF document text
    • http://asirakademi.com/resimler/files/35511597480.pdfIn PDF document text
    • https://schachverein-marchhoefe.ch/fcsr/news/upload/file/sijosopakininelasi.pdfIn PDF document text
    • http://stcforanebanglore.smcim.com/www/js/ckfinder/userfiles/files/29708830820.pdfIn PDF document text
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/89295593994.pdfIn PDF document text
    • http://axiomestates.com/userfiles/file/30010197778.pdfIn PDF document text
    • https://projektovanje.info/userfiles/file/tidezupagewuxanuduxadibu.pdfIn PDF document text
    • http://df-2.de/images/daten/file/nimakokem.pdfIn PDF document text
    • http://vertex-decor.com/userfiles/file/29453876718.pdfIn PDF document text
    • https://collinite.pl/userfiles/file/32479704425.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/mozafobiwarolev.pdfIn PDF document text
    • https://cdmsig1.com/ckfinder/userfiles/files/wuzivemoridut.pdfIn PDF document text
    • http://globalnetworks.de/www.galabau-poscher.de/main/preview/ckfinder/userfiles/files/fupamekojiwimatomogaluliw.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3fe97deb2---vinajafakapiwaf.pdfIn PDF document text
    • http://www.arborvitae.cz/ckfinder/userfiles/files/38810971735.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/76752429492.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/74423286426.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161369d048a79b---71410740848.pdfIn PDF document text
    • http://mtcnx.com/upload/fckimagesfile/pawivobu.pdfIn PDF document text
    • http://leprofit.ee/cmsfile/contentfiles/19178341258.pdfIn PDF document text
    • http://kingsauto-bar.com/js/upload/files/magidukoraravilupojemez.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210908125933.pdfIn PDF document text
    • https://pcetravel.com/files/file/zisefijizemaxozosabaz.pdfIn PDF document text
    • https://sindhuinvestment.com/ckfinder/userfiles/files/9904350460.pdfIn PDF document text
    • http://bygreenpure.com/userfiles/file/guguzerevijelasudozifepud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=soul+full+movie+freePDF link annotation
    • 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_off0000d03e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD03E 10084 bytes
SHA-256: c1f5f5d06cc5f00b378a1b425488adf065c8be3933e04be2c8905fc00f30bc2d
font_01_sfnt_off0000e6bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6BB 20836 bytes
SHA-256: db3af53e3614b0bf121edb5680087ad7f26695fe8007e5f3df79f7ff845c053a
font_02_sfnt_off00011d73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D73 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1