Malicious PDF — malware analysis report

Static analysis result for SHA-256 5e8cf1ac825c8bb0…

MALICIOUS

PDF

114.9 KB Created: 2021-09-03 23:09:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e16f6e643ee2574075a331247eb4972a SHA-1: 2a70fb3fa6db4baf68962e0245667e12a140680a SHA-256: 5e8cf1ac825c8bb0317bc6c84e182afa0740d87402c499df9c30546aff61f09f
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file exhibits characteristics of a phishing lure, using a link farm strategy to direct users to potentially malicious content. The presence of multiple URLs pointing to compromised CMS uploads and disposable hosting, combined with the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics, strongly suggests malicious intent. Although no scripts were extracted, the document's structure and embedded URLs indicate it is designed to facilitate the download of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9889

Heuristics 8

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crysiq.ru/uplcv?utm_term=irda+exam+question+paper+with+answer+pdf+in+english PDF link annotation
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/70ccgvjmg16976sg4reejih3r7/rodisalesol.pdfIn PDF document text
    • https://thealloywheelcentre.co.uk/wp-content/plugins/super-forms/uploads/php/files/3a97c9bfd1d064a607aec805977bdf8c/82893643694.pdfIn PDF document text
    • http://globalnetworks.de/www.galabau-poscher.de/main/preview/ckfinder/userfiles/files/xapewutuzowaberu.pdfIn PDF document text
    • http://khanaphatgroup.com/UserFiles/file/rerixe.pdfIn PDF document text
    • https://deltagroup.bg/uploads/file/24937290378.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210719_6CB19C7466F9701B.pdfIn PDF document text
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612a348b0041a---10115407036.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e875cad524d---wiwumaxupujarenorabaratu.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea3067ec63---55466643893.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/13328a02fe926011dae172f5a167ccee/siwujutapapuxukewojepo.pdfIn PDF document text
    • http://denda.co.kr/ckfinder/userfiles/files/66859624307.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e24f9618eb---paralumomerof.pdfIn PDF document text
    • http://myafmc.com/clients/a/a5/a51d49d85de18111a3d718c63a5e5081/File/folovuvizatokido.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160aca8d457987---34194242308.pdfIn PDF document text
    • https://ultralloy.net/upload/files/5453212459.pdfIn PDF document text
    • https://biocoils.com/img/file/bugoleruririrukawizuvi.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/b7954d05baa5055d0ee535a935e8c017/maferevarejiwawemed.pdfIn PDF document text
    • http://drumlockingclamp.com/FCK_Editor_Images/files/19464241207.pdfIn PDF document text
    • http://universalgroupautos.com/files/others/nuzoxabuzise.pdfIn PDF document text
    • http://planao.com/ckfinder/userfiles/files/82157415080.pdfIn PDF document text
    • https://egf.tw/test2/images/file/vemelotusanitopulu.pdfIn PDF document text
    • http://berallebags.com/UploadFiles/FCKeditor/20210728175234.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/861e6aa9a5288860c54b768ad3947dc7/rulowemazilimevajav.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1722640957---roxogijafekudi.pdfIn PDF document text
    • http://turexpert.md/userfiles/images/file/3181085693.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/13339131012.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_off00015666.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15666 11332 bytes
SHA-256: e9d9998067739d1e442c661da8f62d07fb1b72c06b7fc077c9640302fc370d2a
font_01_sfnt_off00017059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17059 20016 bytes
SHA-256: 5b0a61cc5edc815cef9f57ae146507e88ced7c6f83da5707dfd3e39dfa56fbd5
font_02_sfnt_off0001a506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A506 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1