Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb75baf8dd130a54…

MALICIOUS

PDF

85.8 KB Created: 2021-07-21 16:55:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 4d62cf1d0029a2ca0f77f7027535d73a SHA-1: 56f10f295904a51781de40142c113f387e4dabfb SHA-256: bb75baf8dd130a54fa3efb79f96e3c5487438fc2e5a92bcf65b984e489c42954
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious or compromised sites for further exploitation or phishing. The document body is unreadable, but the heuristics and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://fatamorgana.fr/uploads/assets/file/95204476725.pdf In PDF document text
    • http://www.kreasoft.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160c8710b7b62a---vaputagunokurejumorolof.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f2b85c676---37702917534.pdfIn PDF document text
    • http://kmsenior.org/file/files/76842880207.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/51356382626.pdfIn PDF document text
    • http://americanpetrochemicals.com/customers/CMS-IMAGES/file/3677247879.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/15920171249.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160cd3429580f6---sikidudepiwunesol.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/sifarofiwirakijavetol.pdfIn PDF document text
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6ddbcaecdb---6041438790.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/f833d99d88569789006e2e6508a1e45b/77968484850.pdfIn PDF document text
    • http://mariopresto.pl/userfiles/file/kalujexoxidamaron.pdfIn PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c97a7fb894f---vizoriseni.pdfIn PDF document text
    • https://agrilaui.com/userfiles/file/dofunixevivovosi.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ab82fa00556---dusob.pdfIn PDF document text
    • http://alde-pace.org/ckfinder/userfiles/files/23225899335.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=slope+word+problems+worksheet+with+answersPDF link annotation
    • 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_off0000ebd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBD1 16684 bytes
SHA-256: f04143abd1d095e831595df7c6a4d5bcc7b25305c5d3bb17db013578183b26d4
font_01_sfnt_off0001173c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1173C 11048 bytes
SHA-256: 07f8ef4ffff2e1011a1981ff96e270d3424fd5f0d671b05f68a8547f997a5335
font_02_sfnt_off00013097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13097 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1