Malicious PDF — malware analysis report

Static analysis result for SHA-256 71827cfbddc71444…

MALICIOUS

PDF

75.4 KB Created: 2021-09-18 03:05:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d53a0114fa6869badc0bdfa412f6a4a4 SHA-1: ee8aa4609a3bde74b301bd6c42e0be5a08dfb948 SHA-256: 71827cfbddc71444a0c20f74910066bb4325654d19eede11d8facb27e7a9449c
164 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 compromised WordPress upload storage or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution through these links. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614407f64799b---27973424519.pdf
    • http://jedzenie365.pl/ckfinder/userfiles/files/51076350921.pdf
    • https://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/5844887396.pdf
    • https://amadesafar.ir/basefile/amadesafarir/files/levaxudixixovowaxubedaguj.pdf
    • https://holocaustresearch.pl/nowy/photo/file/rasumokubutelovuzilimavin.pdf
    • https://darkoyunpin.com/calisma2/files/uploads/jodunoxebamutife.pdf
    • https://learnrkbin.jugalbandiresearch.com/ckfinder/userfiles/files/38678492633.pdf
    • http://vagtteam.com/userfiles/Files/ximinakidu.pdf
    • https://alcoquimicos.com/ckfinder/userfiles/files/fukimunusuruvezizexavoba.pdf
    • https://staging-info.sharkovinkom.com/sharkovinkom.com/ckfinder/userfiles/files/52901210163.pdf
    • http://thucancakoihikari.com/luutru/files/rudoxuguxomosovukes.pdf
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f819dceb8---gubesixalupuruwineru.pdf
    • https://unicon-msk.ru/data/files/sorakupalukolikevesamutop.pdf
    • https://cobrawire.com/userfiles/files/38677644443.pdf
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16141ce9420015---63763966205.pdf
    • https://shirbandifelt.com/userfiles/file/zipebalen.pdf
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/60264526377.pdf
    • http://ybshajiang.com/userfiles/file/2021-09-17/2109172231299074875mg625wbs5p1.pdf
    • http://shukokai-voves.fr/userfiles/file/4359782305.pdf
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/10725542611.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143168132122---dadofetulopok.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/6b8a298967a0797f6cc10ddab1cd0a5f/buteditatuvisovoda.pdf
    • http://gaishachuukobuhin.com/js/upload/files/tafegarumejozita.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1614018a3b9f89---filasugawuzejirojejipigif.pdf
    • http://dungcucaytrong.com/images/files/78776526012.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=online+video+to+mp3+converter+and+cutter
    • 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_off0000c467.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC467 16792 bytes
font_01_sfnt_off0000dc79.bin
bcf50bfcf90278af035ee9394016aaa8628c0394d5504adb3fdc5cf615c56739
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC79 16280 bytes
font_02_sfnt_off0001065d.bin
d20cb9bdbcbee8cb5bba4966a782df40254fb3a1e87c47a75768443980ae136c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1065D 10872 bytes