Malicious PDF — malware analysis report

Static analysis result for SHA-256 25de8ec1cd2253da…

MALICIOUS

PDF

86.4 KB Created: 2021-07-04 20:56:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 92634c346b8370a7b5578349c59929ef SHA-1: 37b24a2d3094ddd7c58b13196694309993f09572 SHA-256: 25de8ec1cd2253da023424060e9587e17c2b486469fe0d87fb72bc625ea90278
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF that contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting. These URLs are designed to lead users to further PDF files, indicating a link farm used for phishing or malware distribution. The ClamAV detection and ML classifier strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://bukharaalpharetta.com/sites/default/files/file/22235439140.pdf
    • https://suadienlanhhanoi.net/upload/files/993647074.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608138ee2ea92---peretokutofuruwetemit.pdf
    • https://angelsstaff.com/uploads/file/nakogefexelofovevok.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a3e770c87f3---64059390846.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/u8foqfl65s716a407ekd233vb7/77057129682.pdf
    • https://yepsell.com/userfiles/files/tedasatelalusupipilon.pdf
    • http://dchs1961.com/clients/871949/File/45479589719.pdf
    • http://churchtextile.com/userfiles/file/26641059573.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609651f2aece1---76613980745.pdf
    • http://shinies.ru/img/lib/file/86233095009.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160857e27333e8---kidozadubezozepobepirix.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/a96403c28653aa322b56a62f87322abe/26644072500.pdf
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/6d7e7d351b8ed012d540e9c0491152d1/53059848541.pdf
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607da607b9735---1462098395.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160765f36a5204---xemafavifu.pdf
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160846732160ff---maveturegiwudovukoduj.pdf
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/fsqvv9t5qle3dd09ml4vg1qbq6/jotumifemepuziroset.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/rgu2f752h3j77439i53ds6d2p6/62368593884.pdf
    • http://pampa.be/uploads/userfiles/files/33621572988.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609503fe907db---80270735346.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=houses+for+sale+crookston
    • 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_off0000ef43.bin
baf7aa54f758966eb3a7380e71f83d56d536411805eec142abc45085db3c21e4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF43 10420 bytes
font_01_sfnt_off00010712.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10712 16792 bytes
font_02_sfnt_off00011f24.bin
e325d1397c56a42dcfd9779662a4eda78ec5b0145634a61edccba3feff4994b4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F24 17420 bytes