Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca2d599a0f28261b…

MALICIOUS

PDF

84.9 KB Created: 2021-07-08 10:14:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dc5b8bca73112e9b32da9e675bd705c4 SHA-1: 7ae5c2132f5abd2f839ebef5b56ad8fd6e1aa1d5 SHA-256: ca2d599a0f28261bd869f2cd8251edd3ea45be5ced05bd5305f888b758dfae84
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous URLs pointing to compromised websites, suggesting an intent to redirect users to phishing pages or download further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a deliberate attempt to create a large number of links on potentially disposable hosting, further supporting the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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
  • 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.
  • 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://krisoc.ru/uplcv?utm_term=ventricles+of+the+brain+contain
    • http://alexforstarlight.com/clients/4/41/4125d763bdae894b2c088b8c4c0f4705/File/50814163668.pdf
    • https://lifesmart.ro/ckfinder/userfiles/files/nulusepamapelo.pdf
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/d0406ef3cc93914b68771d5074335123/68130846577.pdf
    • https://cometsecurity.in/admin/userfiles/file/94621661938.pdf
    • http://ash-graphy.com/userfiles/file/wigodibupizenavijisi.pdf
    • http://expresskaliski.info/file/95609335605.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f222c4dd4e---20125301842.pdf
    • https://mimpi1pusat.com/contents//files/movugunibewasegifijaxuze.pdf
    • https://allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a598f1d82e8d4b8668ed99997c4ff8a3/dirinipuxagi.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7a6199566---gosonujozoxanesoxiruje.pdf
    • https://www.jemelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f9eaad0a5---96052794904.pdf
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/5c24b544cefa019eaee76b54bfaac0af/94628591233.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dffdb44c090---misurijagivesorijusomol.pdf
    • http://assushop.com/userfiles/assushop.com/file/gogazuwidojitujof.pdf
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/defa30f901f3522be6a7f1de78bdecc0/lamamiwani.pdf
    • https://lescourailleurs.com/upload/editor/file/79156112015.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9efb3b8d7---nipupivuvafex.pdf
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160abdd6a13cdb---27307307311.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/9017826d81112161eacfada7f66f865f/bowimoxevojefig.pdf
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/h9mhn9k2j25s5v9vbf26vjhgo0/niganepigose.pdf
    • http://bbdecontra.com/userfiles/files/17947922621.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_off0000eba9.bin
d07a3fd5452f0ddcd44e73bca5742366ad1c51c5d6347ae61bffa2a53354aaea
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA9 10544 bytes
font_01_sfnt_off000103ac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x103AC 16792 bytes
font_02_sfnt_off00011bbe.bin
e7bf4784a8a0b07781d36bd86bc827fdac7e7e1856ec47ee4fd4eeee588c5508
pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBE 16508 bytes