Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd0b13e85d06f058…

MALICIOUS

PDF

74.5 KB Created: 2021-09-07 08:52:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4e89ae46c310eabd172ab79c72388396 SHA-1: 5e80957c7dde3be4de8c86d644d9f13c65fd866f SHA-256: cd0b13e85d06f05802bc36843aa53c5ea3deec12c9a381529a5ae162228f9853
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for malicious PDFs. It also contains numerous links to compromised websites, including those hosted on disposable domains and compromised CMS uploads, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to malicious sites for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://coretry.ru/uplcv?utm_term=potential+and+kinetic+energy+worksheet+answers PDF link annotation
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/hn763f3e2n1vnpspoua37qno0m/52194947143.pdfIn PDF document text
    • https://giorgiosantinelli.it/file/wipezotodiregefofimoranez.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/fd07caacccb16284696c9f1c425d4d5a/29219090734.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/didilam.pdfIn PDF document text
    • http://burningspearmarketplace.com/js/ckfinder/userfiles/files/63189288525.pdfIn PDF document text
    • http://hevolta.com/upload/file/ruwizevog.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160b2d54b610e0---rikufupenusozebaxukubu.pdfIn PDF document text
    • https://www.gpaci.org.br/cms/ckfinder/userfiles/files/pijavevovuzakuvexew.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1607292371097e---84466758067.pdfIn PDF document text
    • http://toshiba-center.ru/uploads/files/72317093104.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/22412511038.pdfIn PDF document text
    • http://www.guaitoli.eng.br/wp-content/plugins/formcraft/file-upload/server/content/files/160aa9c651e146---giwodikamegelib.pdfIn PDF document text
    • https://www.rydalmereprestige.com.au/wp-content/plugins/super-forms/uploads/php/files/3eoh28dbidb8gt3l00qucq77b0/6405913060.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ef4e08b256d1a4647ec0c6804a163e23/jirokugusipekunemev.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c264b835cc6---gawodanepuzonurovukewaxa.pdfIn PDF document text
    • http://gapoom.com/upload/fckeditor/file/webuleter.pdfIn PDF document text
    • http://minhanh.com/files/xusugovul.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/12335945774.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/26574338336.pdfIn PDF document text
    • http://hidropro.hu/upload/xakafisojixisiwas.pdfIn PDF document text
    • http://delaneyllc.com/ckfinder/userfiles/files/kosulod.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/28911003807.pdfIn PDF document text
    • http://patp1ryb.ru/media/file/47522714628.pdfIn PDF document text
    • http://lalinpress.com/ckfinder/userfiles/files/31599650612.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_off0000c038.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC038 16648 bytes
SHA-256: 8807bcc662b101d834156951548baa39ca3fd6c28a01fc72b40a8c2cf789c860
font_01_sfnt_off0000eb0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB0E 10940 bytes
SHA-256: 1b2b4fe964654e85b7f66e014cc3244351971ccb35fb30800ff9a74beab44a4e
font_02_sfnt_off0001043f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1043F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1