Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc761366c4851814…

MALICIOUS

PDF

80.0 KB Created: 2021-09-22 19:37:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9c782731661e6a266dca1a34e1225190 SHA-1: e04132c3d83a3e2d38067bf04d1cb6b7238a591f SHA-256: dc761366c48518140e8c27f31e96ee21957066f2cf2e949ee93e77c2f9082751
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple links to compromised WordPress upload storage, suggesting an attempt to host and distribute malicious files. The presence of a 'download button' heuristic further supports a lure-based attack. ClamAV detection and ML classification confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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.
  • 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.
  • 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 http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/161410d6b7ec39---berif.pdf
    • http://zenobiacultura.it/userfiles/file///9668582762.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/838446a6b7ce22d1599e930a954fc159/44962761264.pdf
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/e7q7i576nuounrgi8cibhe6s33/65408112993.pdf
    • http://niestachow.pl/data/aktualnosci_imgs/file/naxevikidevokivolifogomos.pdf
    • https://guanlai.tw/uploads/files/202109151128367449.pdf
    • http://emannsltd.com/userfiles/83430013594.pdf
    • http://studioagm.it/userfiles/files/fewarubi.pdf
    • http://europavloeren.nl/siteimages/file/pumomaduvagaj.pdf
    • http://vers-ma.de/userfiles/file/55505542698.pdf
    • http://kingkady.com/uploadfile/files/62099985246.pdf
    • https://rakowka.pl/userfiles/file/voref.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161446db79046d---90907980632.pdf
    • https://abctranslink.com/ckfinder/userfiles/files/21253199871.pdf
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/sisopitovuwepuv.pdf
    • http://volamthienha.top/userfiles/file/faxaxupififowobivefifa.pdf
    • http://libertyquad72.fr/userfiles/file/15966573796.pdf
    • http://thekitchendesignstudio.org/uploads/files/37153159958.pdf
    • http://boracayg.com/FileData/ckfinder/files/20210919_36ABE54418469C7B.pdf
    • http://partnercable.hu/files/fasumofinesibapobopojafij.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161301c6186a03---71760995744.pdf
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/bjspl74kunpoo5he5mv4iqo4v0/panelomikemoloparamu.pdf
    • http://hotspot-usa.com/js/upload/files/vokalon.pdf
    • http://studioriboldi.eu/userfiles/files/2818815321.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=free+download+thoptv+app
    • http://cluster006.ovh.net/~greeters/be/ckfinder/userfiles/files/wudenaburuwukogi.pdf
    • 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_off0000d715.bin
2bae0572d008a83e6681a4bc2d838becef9c796210c193b5f7cfd0c8baf8d906
pdf-font-stream PDF embedded font (sfnt) at offset 0xD715 17288 bytes
font_01_sfnt_off00010368.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10368 16792 bytes
font_02_sfnt_off00011b7f.bin
4cf375f40246cd050efbeb347f6fefad643b151121205649163fa162cf3b87d4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B7F 10356 bytes